http://www.nationalfootballpost.com/2009/03/behind-the-measurements-height-vs-arm-length/ (http://www.nationalfootballpost.com/2009/03/behind-the-measurements-height-vs-arm-length/)
Here is his chart, the article then lists all the top OT prospects along with their arm lengths
Remember the year we got Elli?? Robert Gallery was one of the highest ranked players ever for OLman. Seems that the thing the scouts missed was his inadequate arm length. I wonder if that conclusion isn't father to your post.
Much like 40 times with Receivers, long arms can be an asset for an OT, all other things being equal. Robert Gallery's struggle at OLT has involved a lot more than the length of his arms; his lack of sufficient lower body strength being most prominent. They, and a whole lot of others, who had him near the top of their boards, seem to have missed on both of those factors.
In any case, I guess there is no denying that guys estimation that 33-33 7/8 is average arm length for OTs. Three of the top 5 OTs in this year's draft: Jason Smith, Michael Oher, and Eugene Monroe have just the arm lengths to prove it.
Cheers!
Here is this year's article on arm length (with this year's rookie OTs being listed)
http://www.nationalfootballpost.com/Measuring-up-height-vs-arm-length.html (http://www.nationalfootballpost.com/Measuring-up-height-vs-arm-length.html)