This is probably an off-the-wall question, but ...
I know that the standard practice is to use DC when TIG welding steel, and AC when welding aluminum ... but a recent thread reminded me that it is possible to TIG aluminum with DCEP. So -- is it possible to TIG steel (mild or stainless) using AC? What would the disadvantages be? Any conceivable advantages?
I've only done a little TIG welding, and loved it, but I don't have any sort of TIG machine available to me at the moment, so I'm just asking to further my welding knowledge (or in my case, to dispel some of my vast ignorance!).