I'd try to find a collaborative source for the 1:1 dilution that agrees with Massive Dev Chart. Most of their times have been good as starting points for me with various chemistry and film combinations, but they do require tweaking on occasion. The Kodak times are the best bet. As far as whether D76 is a 'good choice' for P3200, that depends on the look you're going for and what your subject matter was. Some of my favorite shots that I've ever taken were hand-held P3200 at night pushed to ~12,800, processed in D76 because that's all my school had. The grain is huge, the tonality is great, and my depth of field was really shallow because it was close up portrait work. It all contributes to making images that look like a half-remembered dream and I love them. If you want something sharp, crisp, and really high contrast, TMAX developer is probably a better bet.