It's certainly a grey area and difficult to know where to draw the line....either for your own personal ethics, or the gov't with legislation potentially limiting the technology.
I have heard of reports from the US of guys Musky fishing with 4 to 6 ffs poles on their boat, and just cruising/criss-crossing the lake at 4 to 7 mph. They're not patterning fish (like looking for structure or weed edges), they're just looking for large individual fish they can sharpshoot. Often these are deep suspended fish that you would never find fishing traditional patterns (rock piles, drop offs, etc). Because they are deep, they are often much more susceptible to not surviving release, even when all precautions are taken.
To me that's crossing the line...and I believe that's what the stewards of Eagle Lake are trying to prevent.
Last September my buddy and I were jigging for Walleyes for a shore lunch on Eagle, when a bloated 55"+ Musky floated past us belly up. We could smell it before we saw it. One of the saddest sights I've laid eyes on..