Sorry, I should have specified I'm talking about the Hexamine based stabilizer in the powder press kit. That's the one that I believe (PE said?) contains no drying agent, and is safe for it to be added to.
On another note, I haven't figured out what works best yet, but it seems you do have to be careful when adding time during reuse. If you consider that 15 seconds equals a one-stop push, I'd almost say it's better to err on the side of adding too little time, especially if you're overexposing anyway. I say that because I think I was adding too much time at first, and some of my negs from the first kit came out too dense. I think I was adding something around 15 seconds every four rolls. I think it's safe to say that it's not necessary to add any time at all until you've done at least eight rolls, since the instructions for the (1L powder) kit don't mention adding time within it's expected capacity (of eight rolls).
I'm still trying to decide what to try with the next kit. What have any of you worked out?