I've personally never used rubbing alcohol on bats.. my guess is it would remove a lot of the finish, and the linseed would put it back on.
I use wood stripping products most and follow with lemon oil. There's other products I use, but I wouldn't recommend without seeing the bat you want to clean cause it could do some damage to foil stamped bats. You can also just try 000 steel wool and some lemon oil, that works well too.
Now the decal question.. that's a touchie subject. It depends on the condition of the decal itself. If its flaking you will end up rubbing it off. If you have a nice decal that's just dirty, I would send it down to Bill Rayburn. He's the best at cleaning decals. I WOULD NOT go near a decal with rubbing alcohol. I do put lemon oil on decals though and it does shine them up.
If you post a picture of the bat you want to clean, I will let you know my thoughts. There are some before and afters in this listing
http://www.ebay.com/itm/110597905576...84.m1555.l2649