Here is a question
Is there anyone here that can say that they would recognize a 16 x20 print from a TriX neg and that of a HP5 neg considering the OP test.??
Here's
an answer, Bob.
I didn't want to expound on the OP's test all that much, because I am glad he came to some rational conclusion through his own empirical testing of 120. Good on him, in that regard. But, I've been using both TXP and HP5+ in 5x7 sheets interchangeably for most of the last ten years or so. Both are shot at 200, the only difference being that the HP5+ gets 20% less development time than TXP in PMK Pyro. I pay little mind to which is in the film holder, until developing. They both enlarge exceptionally to well beyond 30"x40". Sure, after working with a negative, I may be able to see some differences in one or the other, maybe even preferences, but most of that is likely anecdotal. Nobody, and I mean
nobody, has ever looked at any of my prints and said, "Sure as shootin', as I live and breathe, by golly, that is TXP (or HP5+

) in pyro!" (As an aside, most people, including photographers, cannot tell my MF prints from my LF prints, even at the previously stated size). A few more lab sessions down the road when I've made other prints, even I can't tell film and process, without digging into my notes. All that is left after the sausage is made is the lingering taste. Either one could go away (likely the TXP), and it wouldn't change a thing either in practice or result for me.
The only other film I use presently is FP4+. Shot only one stop faster, it could easily be my one and only if one or the other of the remaining two films disappeared, even though both the aforementioned films are relatively easier to get focussed under the enlarger due to somewhat larger and more definite grain structure. Or vice versa.