What was initially asked did not warrant this type of response. It makes me question your maturity. If you're applying this cycle, I hope you present yourself more professionally, and more importantly, kinder, during interviews.
The advice you posted would be risky to follow for a great number of applicants.
Columbia:
"Three CONFIDENTIAL letters of recommendation from science professors or one composite letter from a pre-health committee. Additional letters of recommendation from employers or non-science professors will be accepted, but will not satisfy the requirement."
Rutgers:
"Three letters from faculty (two must be from the sciences)."
You are essentially advising students to go against what the schools have explicitly posted on their admissions information pages. I believe in one of the UCDavid pre-dental admissions panels on Youtube, admissions faculty had listed a few things that immediately stand out (negatively), causing applicants to be dismissed - grammatical errors, carelessness (hand-written supplementals vs typed), and not following directions. They stressed planning ahead and attention to detail, including submitting what the dental schools are looking for (letters).
If you feel you have a good letter written by a professional who does not satisfy the requirements, by all means, ask the school to see if you can mail it directly to their admissions office. Don't, however, go based off a gut feeling and send it in lieu of a required evaluator. If believe the evaluator will write a negative letter, you probably ought to haul ass and look for another professional/professor who satisfies the requirement.
