Direct DIE contact is usually different... Back in the early P3 days before the last few runs of P3's when Intel went IHS, and back when AMD still used direct DIE instead of an IHS, most pastes said to thinly and EVENLY cover the entire DIE surface to ensure it was fully covered. There had been issues with portions of a DIE not being fully covered back in the days for manufactures to resort to that method I would say.