Sort of. The surface mechanism in Blitz automatically discards redundant renderstate changes, so the overhead *may* be small - or it may not. If the engine ends up displaying the same sprite 1000 time at different locations, and they all share the same texture/color/shininess etc there will be little slowdown.
Oh good. I assume this applies to all meshes no matter what order they were created in (i.e. it groups meshes by brush to render them).So this means I won't see that much speed up from combining my identical particle quads into one big mesh entity?