I don't really care how other people winterize, my only concern was how 'my' MH made it thru the winters.
I just chime in just like everyone else how I do it and why. The OP can read them all and make their own decisions.
For me, I know when I open the faucet and pink comes out from the fresh tank, I can 'see' that every inch of that line is filled with antifreeze. Blowing out the lines you can not 'see' every inch of the lines to see if all the water is out. Not to mention the water pump issues and the lines related to it. So based on that, that is how and why "I" choose to winterize my MH's.