The mistake that many musicians make when kicking off a tune is they think in terms of “setting a tempo” instead of “kicking off a groove.” Most of the great swingers like Count Basie, Dizzy, Oscar Peterson and the other masters all had a groove going with the melody of the tune in mind before they began the count off. This is far superior and produces greater results than setting a tempo and then trying to find a groove. In the mind of a master, he is already playing before the count off begins. This is very important, so think about it on your next gig if you are the leader. I sincerely hope this is of some help to you.
Best,
Mike