FlyItLikeYouStoleIt
Thank you so much, plasticjunkie, for posting this instruction for the use of Future with decals. You are the only one, other than me, that uses it this way.
Nope, not the only one, I've done this, too. I've used a pool of it, when I had set of bad or questionable decals (IPM's decals in their copy of the Tamiya P-51B come to mind). I'll lay some Future down on the area and slide the decal around just a little bit, before positioning it in the final spot.
I've also used Future to repair decals that lifted or cracked long after the build was completed (EagleCal's "Little Chief" squadron codes did this, don't know why). I use a fine brush to apply it to the spot and secure the pieces of decal that lift or flake off, and then a little more to seal it.