Yes, the chemicals can be reused, at least during the same session. I wouldn't try storing the working solutions though. This is based on my own purely amateur efforts so there may or may not be an effect on density, colour balance, etc. caused by reuse - I haven't got the equipment to test for accuracy and don't care too much as long as the slides look good projected.
THank you for taking the time.
I don't find E6 chemicals cheap at all. But when you add in my present issue it makes sense for me.
I wait until I have enough to fill the drum, but now I have one left over (the 7th roll) so while I need to develop I'd rather not
mix more chems for just one roll. Plus with E6 chems, it's a pain measuring such a very small amount for a 2 roll drum, i.e., 270ml.
I've used it successfully 3 or 4 times. There's info on the tech publications regarding proper extension of time for developers and bleach.
As I got more advanced and took fewer rolls of film, ensuring proper development became more important to me. I'd rather guarantee good results than cut costs. Until that point I pushed chemistry to the absolute limits. It all depends on what you want to do. 5 liters does 20 rolls of 35mm one shot at $2.50 a roll. That's cheap to me.
I just ran my first drum of 3 35mm and 2 120's of the E6 using Kodak 6 bath and it came out stunning. I had one roll of 50 velvia that was pushed so I reran the same chems knocking off 30 pct of the dev time and it worked perfectly.