As long as I can remember frame sprayers in the craft side of the frame business in the UK used to use "varish-fix" transfers, almost always fixed on the last of the colour coats. On top of this went the final varnish or lacquer coat..and that generally was it...no need to bury the decals at all...just to cover them, to protect and preserve them while at the same time giving that little bit extra depth to the colour.
Then of course along came the printed aluminium foil transfers, then the nasty vinyl things that shrank back at the edges and left a tide-mark of adhesive that collected grime..them the equally ghastly self-fix self-adhesive things that always rub off when the frame is held by the down-tube in a bike assembly stand. Although I am very fond of French bikes, I think that the manufacturers there tended to use the worst extremes in decals.
But what is the point of submerging the decals under five or six coats of lacquer? Is it more aerodynamic? It is certainly very expensive both in terms of product used and labour in spraying and "flatting" back. If you really want a flush perfectly smooth finish, without multi-layers of varnish/lacquer, you should try spirit-fix transfers which are as thin as gossamer and incredibly easy to apply. with no shrinkage at the edges. All that's needed after fixing is one good clear coat when a two-pack paint is used.
Norris Lockley....worried about the sprayshop environment..Settle UK