The 3:1 is in moles. I then convert to mg of X to moles of Silver or mg of Silver used.
The Sulfur sensitization is based on the release of Sulfur from either Hypo or Thiocyanate. The Hypo releases Sulfur faster and so IIRC, Thiocyanate takes more time or higher temperatures to get to the same place as you do with Hypo. And what you lose is the fact that Hypo decomposes rather rapidly in plain water and so you have to mix it fresh every time you use it.
Denise has a good example of the Steigmann's solution mixing and use taken from an article edited by Woody Thomas of EK. This is almost exactly that used by Agfa in 1945 for their high speed motion picture film as given in the BIOS and FIAT reports. What you have to do is make sure that the molar ration of Gold to Sulfur is 1:3, and then you must find out how much (approx) to use using the chart in the book and then you have to find the time and temp that is right for your emulsion. As I said above, the time and temp I suggest is 60 mins and 60 deg. If you fog, back off, but OTOH, TAI solution can help as well.
Remember, as I have said many times, finishing (Chemical sensitization) is my weakest point here. I am by no means an expert in this topic. I do know that in the absence of the proper tools, this is very much trial and error.