Well, you could try it and see what happens, but I suspect you'd be happier with a thicker gum mixture. I read through that article, and that's not the only questionable or factually inaccurate statement in it (for example, the idea that one could mix a 30% solution of potassium dichromate --- good luck!) I find it interesting that the person chosen to write this "how-to" article about gum printing doesn't seem to be a gum printer. His work in the gallery at the site is all cyanotypes, and I can't find gum prints by him anywhere else.
Yes, stick with Sam or Kerik.
The traditional standard for the gum arabic used for gum printing has always been 14 Baume, which is a measure of specific gravity rather than viscosity or actual proportions. Til now I've always used liquid gum that has been mixed to the 14 Baume standard, but I'll be starting soon to mix my own. It seems there's some latitude in what works, given that people use anywhere from 1:2 to 1:3 or more; gum:water, but I haven't heard of any gum printers using 1:6 before. I think you should be able to just add more gum to your thin solution rather than starting over, but I hope someone who is more experienced with mixing gum will jump in here.
kt