Doctor’s vs. Conventional Mortgage

This post is an expansion from a discussion with an attending reader who’s considering doctor’s mortgage. Since within the last year I have purchased my first home with a doctor’s mortgage, and then refinanced it to a conventional mortgage. I would like

Mortgage refinance 7 months after buying my 1st home.

This post boils down to Interest saving is guaranteed and tax-free gain, especially sweet when 1. it comes @ no cost/fees 2. it frees up additional cash flow 3. it allows you to build equity faster  4. The above can be accomplished