I'm doing my best to understand it myself,
I tried multiple rolls of tri-x, from the same batch, exposed under similar lighting conditions. Agitated them in my usual way. (continuous for 30 seconds, then 10 seconds each minute at the bottom half of the minute.)
D-76 was 1 to 1, for the listed development time, HC-110 was dilution B for 6 minutes, (I disagree with the 3-1/2 minute listed time. )
D-76 negs came out underdeveloped and thin, the only way I found that I can get decent negs from Tri-X in D-76 is to agitate 10 seconds every 30 seconds and develop at N+2 or N+3. And then they are still not as well developed as they are using HC-110 Dillution B for 6 minutes.
I have spend quite a few rolls of film trying to get D-76 to work for me, and I have used it very successfully tank developing quite a bit of Ilford HP-5+ 4X5.
EDIT: I am also now rating Tri-X (Expired) at ISO 200 and Fresh at ISO 320. I'm going to see if that helps.
Yeah, I don't get that. D76 has been the de-facto standard reference developer for decades for very good reasons. It isn't the best nor the worst at anything but it does a good, balanced job with pretty much all normal films. It's very easy to use. Its life once mixed is far better than Kodak says. A year in a full bottle is no problem. I have some more like 18 months old and while I'll probably mix a new batch just to be sure, the last time I used it a couple of months ago was perfect.
None of that is to take away from HC110 which I haven't used but have a bottle and plan to try. It lasts pretty much indefinitely, even Kodak says "indefinite" in the bottle unopened, and with a pipette or other small measuring tool is super convenient to mix at need. These results, as folks have said, are great. But I don't know why anyone would have problems with D76.
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