I almost went over to that derby this year. I grew up in Jaffrey and know the lake well but the spots I'd want to get to are a LONG walk from the beach and I don't have a snowmobile so I passed.
I heard it's a well run event and the prizes looked great. Was it crazy with snowmobile traffic going through your spread?...that's how I remember the lake.
Traffic was calm compared to past years. Water a foot deep at the beach for about 50' ice 18" thick. Nothing to do with the derby but one dude got a 6-1/2 lb bass while we were there. W-Fat