years ago, I was told (by the rangers)they get to use the bigger motor cause they "claim" it's also used in case of rescue (boat tipping over). Since the ranger was running around checking all the fishing boats for safety gear,which he denied it was just the fishing boats, I commented that if the sailors had they're safety gear they wouldn't need to be rescued.
He grumbled something about not liking my comment, but I pointed out all the boats he checked that day. That one summer I nevew did see him check a sail boat.
I used to idle my 35 HP motor at cowan about 15 years ago, I got away with it for a couple of years. I made a much smaller wake than the boats with 10 HP motors did running wide open. Then I got busted by the ranger and got a $80 or $90 ticket. The thing that really ticked me off was that I had a legitimate need to use the gas engine that day. My trolling motor cable broke while I was across the lake, the gas engine was the only way to get back to the ramp. I tried explaining this to the ranger, but he didn't care. He said that I should of waved my distress flag and called for help.
IMO I think low HP on lakes keeps pressure off and accidents from happening. It would be nice for people with big boats to idle but you know as well as I do that it will just lead to abuse by jerk offs. I'm pretty sure that if your just idling with good reason its ok. I had to do this at Acton lake 3 years ago or so. The ranger asked if we needed anything and didn't hand out any tickets.
You may see a lot of big motors this weekend. The "Fishing Has No Boundaries" charity event is taking place on Saturday (all day) and Sunday morning and participants have clearance from DNR to IDLE big motors around the lake as they take disabled and other folks fishing. I'll be there with my 225, but promise not to throw a wake! This is a great event---I had a blast last year--the folks who participate have a ton of fun just catching small fish and for me, it was great watching them laugh and and have a good time. All it costs me is a little time and gas, and the payback can't be measured. However, I imagine it's a pain for the folks who fish the lake regularly as there will be alot more boat traffic than usual.