I've used one-lift EDT many times. Believe me, it's extremely demanding if you use it with big lifts (and can take quite a toll even with isolation type stuff, according to Staley). 'Only 15 minutes' really doesn't mean anything when you're trying to cram 50-75 reps with a ~15RM in there, especially with more than one exercise.
As for "what can be added safely to PTTP"--I'd say a decent amount. But it also has to be light, easy-strength style stuff (Dan John's 40-day plan is pretty close to autoregged PTTP with more lifts, if you think about it). Combining PTTP with high volume bodybuilding supersets for several bodyparts, even if it's moderate intensity and moderate frequency, is not the way to go.
Finally, 'how much can be done' is highly individual. Depends on your work capacity, recovery, which lifts you're doing, how advanced you are, et cetera. However, spreading yourself across those three goals will not get you any sort of desirable progress. Some things that *could* possibly work, however, if you're absolutely set on doing something along those lines:
1. PTTP for deadlifts and EDT style presses twice weekly (bench/dip/floor press is preferable to standing if you're pulling every day). Maybe an easy set of pullups after DL to keep the groove and help decompress the spine.
2. PTTP 'bear'--deads and presses twice each week. The bear is basically density training, so it might be more what you're looking for.
However, what matters most is your individual circumstances. How long have you been training, what is your best deadlift, and best set of strict pullups, how much do you weigh at what height, do you have any injuries or issues, how many times can you train a week and what is your recovery like, do you have favorable leverages... etc. You can't expect a productive answer from a completely open-ended question.
And thanks Matt, it's screencapped from a vid fellow forum poster Andy took after an SFB course this past Saturday.
