since all timeouts in power management can only be set to values larger than the screen saver activation time, it is impossible to have the screen blanked without locking it if one still wants to lock it during a longer absence. It should be possible to set those times independently, in fact I see no good reason for linking them the way they are. When my laptop is on battery, I typically want the screen to switch off to conserve battery, if I haven't pressed a button for two minutes or so (about the time it takes to read what is displayed on the screen in reasonable font size). But I don't want to have to type in a password every time I look away for slightly longer than those two minutes. However, I still want the screen locked if I'm actually away for some time (say 5 minutes or more).