Hey wait a minute are you saying my vision needs work?

By the way my experience is similar to Ian's above. There's a proposed explanation for this in Anchell/Troop regarding the size of the grain surface and relative to its depth. Apparently Kodak's T-grains are flatter and larger relative to Ilford's Delta grains, which are a little smaller in surface area and thicker. This apparently explains why retention of fine highlight detail and tonality is slightly easier with Delta. In my experience it is splitting hairs though and I use mostly TMAX. Who knows if the explanation is correct, to what degree it makes a difference. After all Anchell also feels the flat grain films are materially inferior in tonality to "traditional" emulsions, and I don't buy this based on the print evidence I've seen.