I did ALA without DMPS or DMSA and it worked for me. I think my symptoms may have been worse than the people that use DMPS or DMSA, but I didn't want to do anything harsh or artifical.
I don't know if Andy Culter would approve of ALA only or not - its what I did on my own.
You could try ALA at very low dosage. Be sure and take the other supplements you need and work with a Naturopath or Holistic Doctor on this. If you are really messed up like I was, you could also have allergy, parasite and infection issues along with the Mercury.