In 4x5, the shape of the H&D curve is different (4x5 Tri-X is TXP, not TX), so the films do produce different results. HP5+ is actually closer to regular medium format and 35mm Tri-X (TX) as opposed to Tri- X Pro (TXP).(posted 8777 days ago)Part of the confusion is that there are two very different films called "Tri-X." This dates back to before WWII when the original Tri- X was a sheet film, and smaller formats used Double-X as their highest speed film. When Kodak discontinued 35mm Double-X in the early 1950's, they called its replacement "Tri-X" but it wan't the same film as the sheet film version.
TXP (the sheet film version) is formulated for studio portrait use with hot lights. This is one reason why there is so much nostalgia among zone system types for the old double-X sheet film, which had a long straight line section of the H&D curve.
IMHO (as a TX user since the late 1950's), HP5+ is much better suited for landscape use than TXP. Of course, that's just another way of saying it behaves more like TX :-)