tried 32/32 recently during my trackday at the new racetrack CIS, i didn't feel any noticeable decrease in grip when i was running 30/28, in fact i'm wearing much closer to the edge now than i did with 30/28 so i guess the higher tire pressures is holding up the sidewall for the profile to work.
i'm going to keep it at 32/32 for the meantime & set up the suspension around it. i have now developed some scallops at the trailing edge of the tires so i guess i need to fiddle with the rebound damping a bit more.