Well i’m noob, so would anybody be so kind and explain this mystery term for me? 
It’s a misspelling of “Tweak” mode. To tweak things (verts, edges, settings, values) is to fiddle with them till everything clicks. There might be a hotkey (combo) for ‘tweak mode’ in one of the prerelease builds and if you tell me what it is I could elaborate.
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I don’t belive blender has a tweak mode
in wings3d tweak mode is where selection immedately enters you into grab mode [and you select with the left mouse instead of the right], so you can just click and drag verts around. It’s useful for doing a lot of small changes to verticies of the model.
I don’t really see a need for a tweak mode in blender because I don’t find it at all annoying to right click then hit g to move the vert. In wings3d unlike blender selecting something doesn’t deselect everything else [kind of like if you always had the shift key held down in blender]
because I don’t find it at all annoying to right click then hit g to move the vert.
RMB-Drag is fluent. And ever since Alt-RMB was introduced as loop-select it’s become like another Gesture.
I think though that one of the SoC era testbuilds had a “tweak” patch. I’d just as soon wait for him to come back and tell us rather than go off searching for it.
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Yes Fligh,i meant “tweak mode” - my mistake.
At Blender.org’s forum you can find bf build with tweak patch (by Bellorum).
http://www.blender3d.org/forum/viewtopic.php?t=7350&sid=baafb467579272d8456a70cb81addbd7
tweak mode is in, but it isn’t activated, I think it requires a setting to be different when you compile to be activated - the reason is that Ton has a particular work flow that makes use of the mouse action that theeth used for tweak mode, so until someone provides an interaction method that ton approves of, it won’t be activated for general usage.
LetterRip
Ok, going back a few builds prior to that one I found:
Tweak is when you click-drag a vert, edge or face as opposed to selecting and then (g)rabbing. There has been a tweak in Blender for a while, however some of us have issues with the implementation. Ton has decided that Tweak mode put too much strain on the wrist, and decided on click-drag-confirm click instead. It’s a matter of preference, I guess, but most non-rheumatics prefer the original approach
So, basically, if you use this build, in edit mode you can LMB-Drag verts without having to select them first (what wings does).
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The difference is quite obvious when you compare official builds to “my” builds. In official, you have to click again to end the tweak, whereas if you build from CVS with the option “export NAN_TWEAK_MODE=true”, the tweak ends on release instead. I’d prefer to have a dedicated tweak mode, though, since tweaking small distances can be tideous, and not so responsive (because of gestures code?).
Anyways, as long as the option is there, I will supply builds for those that are interested.