S.
Contact your state DNR / DEP etc. Here, you're asking for opinions when you need the facts for the states you hunt in. The federal law as presented and cut and pasted from CT's on line web site:
[font=Verdana,Arial,Geneva]"From or by means of any motorboat or sailboat, unless the motor has been completely shut off and/or the sail furled, and its progress therefrom ceased."[/font]
In my opinion as long as it's not motorized your okay. With respect to mechanical drives, I have never seen anything written in booklets from MA, ME, NH, NY or CT. One could also argue that Mechanical is anything that gives you mechanical advantage and the first item thrown out under that definition would be oars. So get the facts straight from the enforcement branch in the state you'll be hunting in. Or you may find yourself paddling by hand.
Scott