The reason your script seems to work is because of fAnimPos. That value includes the bone influence. BUT it doesn't include any information on how much influence a bone has.
The blend poses script in another thread may be something you want to look at. It doesn't use bone influence but uses poses (actions) and blends the point positions of a vector layer. I have had the idea in the back of my head to play with that script for blending bone motion or trying to create my own "fake" bones with influence but have not had the time.
-vern
Understanding Bone Matrices for Evil Purposes...
Moderators: Víctor Paredes, Belgarath, slowtiger
Well, I thought the script worked due to it updates the 0 frame bones position to the be exactly the same as the bones have in the current frame of the animation, and with all this mesh, finally any bone movement influence is nulled or counteracted... just as I wanted! 
I'm not sure how much bone's influence has something to do with all this, but what I didn't understood very well is why bone dynamics worked right under this "special" circumstances... Although now I think that dynamics calculation has nothing to do with 0 frame at all, but (fortunately 
) with frame to frame position/rotation differences, thing that seems obvious now, but at first I had my doubts...
Well, i think I'll try to invest some more time and "effort" in this issue but if things become to much complicated (involving matrices again, i.e.
) I think I'll return to my first method (where were the points current position what was copied to the 0 frame instead) although it means I must use again the "ugly" (but effective at last) action fix that I wanted to avoid... Meantime, I'd love someone had more "crazy ideas" to try or think about
Oh, and yeah! I'm totally interested in poses now that it seems it's possible to access to it via scriptiiing! I think that this added, and the ability to access to the actions too, will be a milestone of possibilities! Hmmm, sorry to heard you are lack of time too
I'm not sure how much bone's influence has something to do with all this, but what I didn't understood very well is why bone dynamics worked right under this "special" circumstances... Although now I think that dynamics calculation has nothing to do with 0 frame at all, but (fortunately ) with frame to frame position/rotation differences, thing that seems obvious now, but at first I had my doubts...Well, i think I'll try to invest some more time and "effort" in this issue but if things become to much complicated (involving matrices again, i.e.
) I think I'll return to my first method (where were the points current position what was copied to the 0 frame instead) although it means I must use again the "ugly" (but effective at last) action fix that I wanted to avoid... Meantime, I'd love someone had more "crazy ideas" to try or think about Oh, and yeah! I'm totally interested in poses now that it seems it's possible to access to it via scriptiiing! I think that this added, and the ability to access to the actions too, will be a milestone of possibilities! Hmmm, sorry to heard you are lack of time too
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