Since it so hot, I've been spending time indoors in the A/C and I happened to re-read the 1999 report on the Fish Creek closures. One thing that jumped out at me (which never happened):
Monitoring of restoration of the Fish Creek watershed is important. As roads are obliterated throughout the watershed a three foot wide path will be left on the old road bed for future access into Fish Creek.
While the "plan" might have been to leave a 3 foot wide path, that is definitely NOT what occurred. The only path that I've seen exists on a few of those decom roads is the double track path that the quads created - and that really only goes down the old 54 road (the one that goes down Fish Creek). The rest of the decom roads have NO path at all. It is truly a shame they did not do this as specified - it would have left a whole series of passable trails in the drainage instead of the choked out alder thickets that are so prevalent now.
The contractors doing this work - I've only talked with one - were instructed to leave a path. No mention was made of size or clarity of the path by the one I talked with. So the results were up to the skill and interest and patience of the individual doing the work. I do not think the FS put a high priority on this.
The top road, which reaches Skookum Lake and the old Baty Butte trailhead, has a use trail at least as far as Skookum Lake from Baty Butte. I don't know if any of it was the result of work decommissioning the road, and it looks like it could have been just from people trying to go from above Lost Creek To Skookum and Thunder Mountain.