PD,
I believe you correct on several counts.  Just guessing at the vintage of the map and the Sharpie red dots, I would say it was from Woods Davis in the 1980's.  The marked site is the one you described on the North shore western most long point or the island adjacent to it.  The story that goes with it is a conversation that took place in Woods's parking lot.  Found a gentleman sitting on his tailgate with a 6 pack and a container of salt killing a bucket of minnows.  He was headed to camp on Cheatan bay the next day and said they would catch 100 lake trout per day with the minnows.  Nothing large, but lots of fun and they only kept a couple of small eaters.  Yet another one of those people I have met and now wonder if they are a member here?

Regards,

Bob