And someone on another discussion forum contributed:
"Pablito
08-12-2009, 14:47
Tri-X was reformulated several years ago when Kodak built a new smaller facility o coat BW films more efficiently in the digital age when film isn't selling as fast as in the past. They actually had to reformulate all of their BW films, and some were simply discontinued to avoid the cost of doing this. At the time, Kodak said the reformulation was needed because of the new equipment that was designed and built for the plant.
Tri-X got less grainy, Tmax 400 and Tmax 100 got granier in my opinion. Tmax3200 stayed about the same. I switched to Tri-X from Tmax 400 after that because Tmax 400 's image quality suffered so badly. They finally redeemed themselves with the new Tmax 400 that is being made now, which is better that the original Tmax 400 and light-years better than the one they made after the initial reformulation.
"This is correct. But it had different effects on different users. When Kodak made that change they ruined Tri-X for me. They made it less grainy, true, but it also lost contrast and speed. The negs exposed at ISO 400 looked thin, which may have been good for scanning but did not make the sort of wet prints I like. I changed to Ilford HP5+ which is much closer to the "old" Tri-X. I am much more happy with HP5+ than the "new" Tri-X."