Apparently,
This is still a misunderstood topic. Unless a Quarterback is 9 ft tall ...he can not throw over any NFL defensive lineman.
Your average D lineman is 6'3" - 6'4" with extended arms add about 2 ft.
Troy Aikman was talking about this the other day, NFL QBs must learn to throw in throwing lanes. Pass blockers try to create these lanes with their blocking schemes.
You don't throw over people - just between them.
As far as arm strength, I didn't think Romo had enough - but he has proven me wrong. He has an ultra-quick release and good deep ball. Think about the beautiful (dropped

) bomb to T.O. in Washington.