Can you have proper extensor action with a bent left arm?

[jim_0068]

Reason i ask is because my left arm is bent naturally as it hangs. Very small, but it is there.

Whenever i try to keep my left arm very straight by using extensor action it creates tension and i don't hit very good shots at all.

However if i use the "pulling of the thumb" and allow the slight bend at the end of my swing the tension is virtually gone and i hit very good shots.

Comments?