A couple of comments:
This mod would be more difficult after the canopy "glass" is installed, but with a little ingenuity it should be possible. All my wiring is accessible. Just a matter of protecting the clear stuff while you're working. Blue tape and paper (maybe a thin sheet of something hard) are your friend. If you don't like the idea of drilling with a big hole saw (nor do I), use a Greenlee punch (perfect holes and no burrs to speak of). They require only a small pilot hole to get started.
And regarding the Defog/Defrost effectiveness. My earlier point was that it does a good job of moving heated air around in flight. Personally, I've never seen any condensation on the glass, but the plane is only a few months old, and this is not an all weather plane. They do move a lot of air, and my system is turned down to about half speed (at max it sounds like you're getting ready to levitate away!). So if you needed more, turn 'em up. Pretty much run mine full time.
In the end, opening the canopy might be enough to clear things up, and it's probably prudent not to go flying before your canopy has warmed a little to help prevent any unexpected IFR. I do think the fans help with more uniform warming. This system is all most useful after your heater is transfering some BTU's and sending them to your feet.
Hope this helps ...
Cheers