Wet sanding & sponge backed discs

I know there are at least a few big fans of wet sanding (LGS and Lignum to my knowledge), and it's a technique that I'll have a fiddle with really soon. The abrasives discs that I'll be using have a very thin sponge backing, and it occurs to me that this will no doubt act as a small reservoir of oil, particularly in the early phase (where I've just recently read LGS saying to initially flood the surface).

So, would that little reservoir be a good/bad/indifferent thing do you think? The sponge is about 1-2mm thick, depending on the grit, and on the really fine grits (1200-4000) it's about 3mm thick (with no paper substrate - just grit on sponge).