Win 7 64 Ult
GeForce GTX 580 1.5 GB
Short description of error
Note, I use a heavily customized blender version that is LMB-centric and uses ALT-style navigation, with a more standard selection set. Also I use a Wacom Tablet exclusively.
But this issue has been confirmed by other users with different configs.
Anyway, anytime I'm selecting an object that is heavy on geo, my click is registered as a drag (tweak).
What is happening. There is quite a noticable lag before even that drag (tweak) event kicks in. I believe under the hood there is some heavy computation going on that takes away the time of the initial (click) event (hence the lag to even trigger the drag event). This is all even more pronounced when clicking on heavy geo. And while the system is frozen with that computation, because I'm on a Tablet my mouse cursor always slightly moves in the meantime and triggers the tweak event, which in my case is mapped to box/marquee select.
I hope this all made sense.
It's super annoying because if you use a tablet it's super hard to find a balance and separate click <> drag events in blender. Next to impossible when clicking on heavy geo!
Possible (quick) solution, whatever computation happens after the initial click trigger, leave them for after you decide weather it's a click or tweak (drag) event. I believe just by tweaking this one sequence of execution the whole event trigger system could become more responsive.
Ofcourse, only in the case if those computations are not something crucial to that same trigger event. But whatever it is, I'm sure there's a way around it to not calculate all the things that are currently done and producing the freeze of the system.
Exact steps for others to reproduce the error
You can test it if you assign different actions/commands to the same MouseButton one for Press, other for Tweak. Create a number of objects, make sure one of them is heavy geo.
Press will be overridden by tweak almost each time you click on the object with heavy geo.
Confirmation by other users starts here:
In general the whole Event Trigger has to be looked into. As Stan Pancakes menitoned, the distinction between Click and Double Click is also not resolved elegantly.