Ok, first my comments on the run:
The best level by far was level 4. You did a lot of play around, there was impressive precision, and both players danced in sync. The rest of the levels, honestly I fast forwarded most of it because it was so predictable. Like the boss of level 5 (and many others), couldn't you hit him in a variety of ways and then kill him at the top of the screen only near the end? I'm almost certain that it wouldn't make you lose time at all.
Also, the lag produced in level 2 surely came from the buggy flames, which appeared because you went too fast (the slow flame that came from the left went all the way to the end). It's obvious that if you waited a little for it to go away and then going to the next section would avoid the glitch, and so the lag.
Also, did you try picking mode A and doing what I do on big blarg in my NES battletoads movie? By that I mean this:
http://tasvideos.org/BattletoadsTricks.html
(trick for NES battletoads, may work on BT&DD)
"Doing 15 times more damage
Hit an enemy or another player until he's almost dying, and prepare the final hit on him, but miss him and hit the enemy that has full health. This last blow is quite powerfull. This doesn't work on bosses (a boss is any "enemy" that will end the level when defeated. This is not the case for Big Blarg)."
All in all my biggest complaint is that the gameplay was too predictable (except for level 4) and cared only about doing the fastest time possible, and even then there are big chances that it can be a lot faster.
I vote no (I wish to see more play around).
edit: you can also do this (taken from tricks page):
"Super high jump on jet and surfboard
To do this, touch the jet or the surfboard while going up a running jump. Basically, run and jump right before hitting the vehicle. "