As many have said before, you need to get the film developed to the same contrast as your Tri-X film before you can start comparing them.

The reason for this is that you cannot identify differences in tonality between the two films until your highlight and shadow points are in the same place. While films have an inherent level of contrast, how you develop your film determines what contrast your final negative will have (because the final result is more a function of how long you develop the film, developer dilution, agitation, and temperature). This is why coming up with developing times that work for your paper and paper developer is so utterly important. This takes observation in the area of contrast levels of the light you're photographing in, how to expose your film based on that, and finally how to process the film to compensate for BOTH. And never lose sight of the fact that you develop film to make sure the recorded tone scale fits the paper - that is how it's intended to work, not the other way around, (which is commonly seen), where printers try to wrestle the paper around the qualities of the negative.


Now, about developer - I use replenished Xtol, and up until I tried HP5+ in earnest (about 20 rolls), I was under the impression I could make every film work in that developer. But I discovered that I don't like how the grain looks using Xtol, replenished or not. But I bought a bottle of Ilfotec DD-X, and all of a sudden I had negatives I liked again. Go figure.


About f-stop printing. It is confusing to think of it in terms of f-stops. I prefer to think of it as doubling your exposure every time you expose a new area of your test strip. 2s, 4s, 8s, 16s, 32s, and longer if you like really dense negatives (I like really dense negatives).
The benefit is that in the lightest and darkest stripes of your test strip, you see things you wouldn't have come near with your regular approach. Highlights that sparkle, and really deep black shadows you otherwise would not have noticed - it makes you see a wider spectrum of versions of the same negative.

The recommendation is - try harder and you will find that HP5+ and Tri-X are a lot more similar than they are different.