I think you are being a little bit generous by assuming the bioavailability of intranasal Ritalin is going to be three times stronger. For one thing, oral BA of Methylphenidate fluctuates quite significantly based on things like stomach contents and intranasal BA is influenced by things like nasal contents.
For another, you need to take into consideration peak plasma concentration when thinking of tolerance. Peak plasma concentration is the maximum level of the drug attained in the blood stream. So, let's say you take 50 mg of Ritalin orally. The Methylphenidate will peak in your blood stream, but the peak will be more gradual and probably less pronounced than if you insufflated the same dose. This is because when you snort the Ritalin, more of the drug gets into your blood stream at once. The amount of drug your body is exposed to at a given time will have quite an impact on the level of tolerance it builds.
So, while in theory you're idea may make good sense, I'd be willing to bet that after a few days of snorting Ritalin, 50 mgs orally won't do shit for you.