Charley:

Well, you're right that the WR should be out of the water at anything over taxi speed, but it's likely to take a dip when you rotate, especially if abruptly.

As far as your post starting "seems counter productive": P-factor makes the plane turn left. Rudder drag on the left float makes the plane turn left. Right rudder is used to cancel left turning tendencies. You might be right about the rudder drag balancing the P-factor, if they happened at the same time and if the value of the forces were the same. But if I'm having to hold a little right to taxi and then still a little right once I lift off, I feel like I'm less likely to get crossed up. ALSO, the muffler on most planes makes the right wing a little heavier so adding accessories to the left of the plane would bring it closer to balance. But these are all low-order effects, and probably make no noticeable amount of difference anyway. I just hope your plane flies well and you're having fun!