I think the biggest problem with developing prints in film developer is capacity/ expense. It takes a lot of developer to develop all that silver in a print, and film developers are not formulated for that, so one has to replenish frequently and at considerably greater expense than a typical print developer. If one compounds one's own developers, then all bets are off. I've committed every sin known to man or beast in my darkroom, and learned a few lessons in the bargain. For instance, a clean working, staining film developer also makes a fine direct toning print developer, although I admit I cheat in its compounding for the respective uses. I even formulated a universal developer I liked very much. I called it, "DeFehr Rapid Universal Developer for Film and Prints" as a play on the hilarious product names from the era when universal developers were popular, but few got the joke, and some ridiculed me for naming the developer after myself (as if it were a real product!). The developer resulted in my use of a few stock solutions made up in different proportions to make a developer for either film or prints. I decided it would be fun and potentially educational to try to come up with one formula that worked for both. I was very happy with my solution to the problem, but it did involve some unorthodox quirks; in print strength, it developed most films to normal contrast in about 70 seconds! My oldest son, who was new to darkroom work and hadn't yet formed any prejudices about how long it should take to develop film, loved it, and wondered why anyone would want to develop their film for longer than 70 seconds. Used with Superfix in my Jobo ATL3, I could process film from start to finish in about 3 minutes. When I published my formula with development times, I met with all the expected objections: it would produce huge grain, poor gradation, and uneven development, and the short development times would demand too much precision in timing. None of these objections had merit. Grain was similar to D-76 1+1, gradation was very good (I used it for portraits), I never saw any evidence of uneven development (even with stand development!), and my novice son had no trouble with the timing. Granted, we were printing on VC paper, which afforded us considerable latitude, but who doesn't print on VC paper? It was a valuable learning experience, and a lot of fun!