There is no cheating except with a digital camera :-) With Muriatic Acid enlarging might become difficult - dodging might be done, but the developer already burnt the negative...
Adding other chemicals to combine their special benefits is okay for me, as long as the developer produces better results.
David, you are right, but as I said in the beginning, one of the interesting aspects of "Java" developers is that they are not toxic, and dumping used devloper into the sink is not a problem. With Pyro developers this is very different: they are pretty toxic, and at least here in Europe it is off limits handling it like a harmless fluid.
When you combine Muriatic Acid (AKA Hydrochloric Acid) with Sodium Hydroxide you end up with Sodium Chloride, water, etc., etc. (Kinda like Microdol-X).