after reading and "meditating" over this entire post for hours i find problems with a number of instances. the first that arrises is the perpetual argument within this post amongst applying absolutly no upward force with the bottom arm
(reference)
http://www.youtube.com/watch?v=DYaBPDTrVuI
bubka the "prophet" in this video. may have his arm bent, but it still seems to me like he is applying upward pressure for at least a fraction of a second to engage the initial pole bend. his hand may have been at his head but this was (what i believe as an error) later corrected on his part.
Secondly
in the same video after bubka finishes his take off. his arm continues to straighten! Now unless you are refering your immediate pull after the take off to "rowing" . The bicep
MUST bend the elbow continuily.
UNLESS you pull with your lats or with your upperback due to a retraction of the shoulders. If you analyze this video you will see bubkas shoulders certainly do
NOT retract. as a matter of fact there pulled
FORWARDS. so that eliminates pulling with the upper back. secondly pulling with your lats can only occur when shoulders are retracted. otherwise all other efforts to pull with your lats just make you "row". (if u dont believe me stand there .. extend your arms and try to pull towards your chest abs or hips with your lats without a shoulder retraction. it doesnt happen). so he could not have been pulling throughout the entire vault. and obviously if his lower arm is straightening throughout the vault (he may not be pushing) hes certainly not pulling with it.
now lastly say someone performed a proper takeoff and pulled directly with the left arm after the takeoff was complete. ok ..... ok.
now the affect that would have on someones inversion would be detrimental. not positive.
http://www.youtube.com/watch?v=Ov4gjUf6fZI
this is a video of a very dear vaulter of mine. granted her takeoff is certainly not free. BUT as you explained if someone finishes there takeoff and pulls with the left arm it would speed up there swing rotation and get them inverted quicker. now sandi has a VERY fast pole run. (shes one of the fastest hurdlers in the nation). and she has plenty of pole bend wich would have allowed her bottom arm to naturally straighten as bubkas would. But shes pulling directly through her bottom arm in her vault and that keeps her arm exessivley bent. and as a result of an early pull it raises her shoulder level to high for her to properly get inverted.
correct me if im wrong but according to my analysis bubka obviously wasnt pulling. and if you continually pull from takeoff it will displace your shoulders. leaving them too high and your hips to low to invert affectively