Dullcote will protect against chipping, just not fabulously.
Sorry to correct you, but it will actually do nothing to protect.
Dullcote, for want of a better term will "frost" the layer it hits.
Think of gloss varnish as glass. Its shiny and smooth.
Dullcote turns it to frosted glass. It etches tiny bumps onto the surface, stopping it being shiny.
Its technically damaging to paint (being highly solvent), and I believe there are a couple of fantastic photos of plastic models its devoured.
Its currently banned in the EU (which annoys me as I need another can) its apparently horribly effective because its full of horrible chemicles.
I seem to remember it being stated that its got the chemical makeup of diesel floating in alcohol.
But I digress. Put on a gloss coat (GWs gloss was damn nice, but discontinued) , then dullcote it
AFTER TWENTY FOUR HOURS for a good finish.
Spray it too soon and it can crazypaving effect your figures...