I agree that having some default values saved (and persistent from one
session to another) could be a good idea in several cases.  This would
apply to the compression options and other parameters for the file
formats.  This could also apply to the default selection of flattening
vs. saving a single layer in the Export dialog, so that you only have
to press Enter when the dialog pops up, without having to worry about
moving the mouse over the right button.

But I do not think that having an option to skip the dialog is a good
idea, especially if it would be necessary to find the appropriate
option in the Preferences dialog or in the menus to re-enable it (and
re-enabling all dialogs at once could also be annoying for the user).
Saving the default values is fine, but hiding the dialog can be
confusing: if a casual user of the GIMP has to save a lot of static
GIF images, he would probably set the defaults for the Export dialog
to flatten the image and convert to indexed mode.  Maybe he checks
the box for skipping the dialog next time.  A couple of weeks or
months later, he wants to save an animated GIF.  He has forgotten
about the Export dialog (because he does not use the GIMP very often)
and now he is confused and he cannot find the way to save the animated
GIF image.  The same could happen with any other option in the Export
dialog or even in some file format parameters.  So I think that the
ability to skip some dialogs could do more harm than good for those
who are not using the GIMP on a daily basis. On the other hand,
setting the default values appropriately would already help a lot
because you could simply press Enter without having to spend too much
time selecting the right options in the dialog.

If you agree, I would like to consider only the first part of your
suggestion and change the title of this bug report to: "Add persistent
defaults for the Export dialog."  The persistent defaults for the file
formats are already covered by bug #63610.

Actually, it's more the skipping than the persistence that I want.  In
the case of the mentioned dialogs, the non-persistent defaults are
already usually "the right thing" for my purposes.

I'm trying to reduce the number of popups that ask questions. 
Questions I've answered before.  Questions I've never varied my
response for.

Here's a compromise:  add yet another global flag, "make dialogs
skippable," defaulted to off.  If that is off, always show dialogs and
don't show the "skip this" checkboxes on them.  If that is on, skip
dialogs that the user finds annoying, and show checkboxes on the
dialogs that the user might find annoying but has not yet decided.

While this all may seem to be new and strange to GIMP users who have
not touched other platforms in a long time, this is a pretty
conventional scheme to avoid clutter.  GIMP could use a lot of
uncluttering by letting the user decide what is important to them and
what is not important to them, and to become the user's assistant
instead of the user becoming the application's assistant.

Make software smarter.  I'm not saying "make the software second-guess
the user and make assumptions," I'm saying "let the user authorize the
software to be the user's agent."  A clean workflow means no
unnecessary interruptions on tangent trivialities.

OK, since you care more about the skipping than the persistence, I
will keep this bug report focused on the skipping and I have submitted
a new bug report about the persistence (bug #75459).

Personally, I do not think that skipping the dialogs is a good idea
because it could cause some problems for those who do not use the GIMP
frequently and who could be wondering why some feature is not
available to them.  Being able to skip unnecessary dialogs may be
nice, but only if you are unlikely to ever want to change the options
in these dialogs.  I change the options in the Export dialog boxes on
a regular basis, especially when I switch from photo-editing work to
web work (including some animated GIFs) so hiding the dialogs would
not help me.

By the way, I understand the concept of skipping unnecessary questions
quite well (why do you think that there is a "show tip next time GIMP
starts" checkbox in the Tip of the Day dialog?).  But from my point of
view, I think that skipping the Export dialog could do more harm than
good.  At least I am glad that you are not proposing the Windows 2000
way of having the application or OS deciding automatically what should
be hidden from the user.

Besides the risk of confusing the users who forgot that they had
disabled some dialogs several months earlier, there is also the
problem that there is not one, but several Export dialogs.  The dialog
is built dynamically depending on the current features of the image
and the features supported by the target file format (so you get
different questions if you are attempting to save a multi-layered RGB
image as GIF or if you save a layer as PNG when the opacity of the
layer is less than 100%).  If the user selects to skip the dialog,
does he mean that he wants to skip only that combination of options
for this target file format, or for all file formats, or any
combination of similar options for this file format, or...?   And the
last problem is the implementation of that feature, because it would
affect several parts of the code (export function, preferences,
parasites, file plug-ins).

Another thing that I forgot to mention: saving an image directly and
saving it via the export function causes a slightly different behavior
from the GIMP (file name, dirty flag).  Skipping the Export dialog
might make the user forget about these differences and then the
behavior of the GIMP may appear to be inconsistent if the user is not
aware that a file was exported instead of being saved normally.

I would not put a skip question in the dialogs, but put it in
only one place, the place where you turn the thing on and off
(Preferences). So people do not get problems about how to enable
back after disabling, cos both are in a single place, no "how do
I get things back?" (or at least not as complex as a two place
system is).

GSR
 

I am wondering what actions one would have to take to get many dialogs
popping up asking you questions on export.  
I am also wondering how these dialogs are desinged and if it might be
appropriate to redesign and merge them.  

Please describe and or provide screenshots, maybe we could mockup a
better design.  

Try to save a grayscale image with multiple layers and perhaps even
layer masks to a not-so-versatile image format and you will get a
chance to see the Export dialog (which definitely needs a UI design
review).

Instead of a "skip this" button a better solution would probably be to
have a section for the write/save options in the preferences dialog.  

In addition you could add a generic Advanced/Options Button to the
Save/Export dialog that would take you to the relevant options dialog
for the current file format (or if the file format is set ot By
Extension it would just show you the Save options section of the
Prefernces dialog).  

This solution would require quite a lot more effort and could not be
done as quickly as a simple 'skip this' button but if you do add the
'skip this' button/checkbox then you will need some way of disabling
the bits you have skipped so the Preferences work would probably need
to get done eventually anyway.   
 

Changes at the request of Dave Neary on the developer mailing list.  
I am changing many of the bugzilla reports that have not specified a target
milestone to Future milestone.  Hope that is acceptable.  

I think This behaviour would be nice - holding shift while pressing the "save" 
or "export" button should skips rest of the messages. If using keyboard on 
export dialog, shift enter must do the work of skipping the rest of the 
messages.

I cant state strongly enough how much of a bad idea i think it is to need
checkboxes for skip this (with the exception of the "tip of the day" it really
shouldn't be needed anywhere).  

I still much prefer the idea of having good defaults/preferences for
import/export and to have an options/preferences button in the save dialog to
give easy access for those who want to change the defaults. 

Laxminarayan Kamath: I could probably script something for you that didn't
prompt you for anything and just created a nem file
Untitled-???random-number???.xcf in your homediretory.  I think implementing
your suggestion would be ignoring the need to streamline the existing process.  

I agree with Alan here. Jimmac's proposal for an overhaul of the Export
functionality is a good start
(http://primates.ximian.com/~glesage/wiki/doku.php?id=gimp:png_export). It needs
some more thought because it just won't work the way that Jimmac suggested it.
But it's this sort of workflow analysis and detailed proposals that we need
here. I don't think we should try to fix Export by adding to the existing
dialogs, we need to reconsider the whole thing.

And I also agree that adding "skip this step" checkboxes to all the dialogs we currently have is a wrong way to attack the problem. I'm closing this as WONTFIX now.

Just for reference, here is the save + export spec currently being implemented and that addresses many problem mentioned in this RFE:
http://gui.gimp.org/index.php/Save_%2B_export_specification