I'd caution new riders and buyers not to rely on other people's formulae for what will fit you. In the end they are just other people's opinions. There is just no substitute for riding bikes of different size and seeing what actually feels good to you. I've never seen anyone's fit scheme that would provide a comfortable bike for me to ride. Measure the bikes you ride in a consistent manner and soon you will see what works well for you and what does not, get a small tape measure that reads both inches and Metric and carry it when you are out looking. Take some measurements other than the ordinary ones you hear about. Measure from the BB crank center to the saddle top, for instance. Do your riding and testing with this adjustment rather uniform once you find out what feels good to you.
Folks will let you ride their bikes. Vintage collectors are generous that way as a rule.
If you have a bad lower back as I do, you may find that you will want a considerably larger bike than others think you will ride. Too many variables enter into it for someone else to tell you what will fit you.
No substitute for riding different bikes.make every effort to do so. Eventually you will be able to ask good enough questions to buy a bike unseen and have it fit. At least usually. Bear in mind what you are buying.a Crit bike will offer a different feel than a Touring Bike, but that is a much deeper discussion.
Of course, that's just my opinion, too.
Tom Sanders
Lansing, MI USA