Refinancing every 4 years?
Who the hell would do that, unless you're strictly looking at reducing monthly mortgage payments, and not factoring in the overall costs involved in the refinancing. Or, you got a shitty initial loan.
The brief time I spent originating VA streamline loans was eye opening. The company I worked for folded all fees (including origination & closing) into the loan. Presented as a "no cost" refi.
The interesting part was folks would refi to save $20 - $40 per month. Sometimes the savings was greater, maybe $80 or more in monthly payment reduction and they would balk at the refi . . . they knew there must be a catch. Crazy.