Ok, so I've spent some time on the right pec drill, and I definitely feel like I've made some progress:
During this session I was throwing slightly uphill on pretty muddy ground, so I wasn't going at them full whack.
I still think I can delay the hit a bit more, but there was definitely a better feel to the throws
3 drives, with slow repeats:
http://www.youtube.com/watch?v=d02l7Y0lhGg&e
1st drive - Teebird, early in the session, not a great throw ~ 330'
2nd & 3rd drives - Wraith, good throws ~370'
For reference, here's me circa June 2007 when I first asked for advice on here:
http://www.sandblaggers.com/Video/BruceDrive1.wmv


