winterizing

Yes, if done properly both methods can be effective. 

As long as you use the winterization valve and house And don't put the pink stuff in the fresh water tank, the de-winterization process isn't much different. You would need to run fresh water through the pipes until the water runs clear. I would assume the hot water bypass would be set either way, but it is more important if pink stuff is used as it will corrode the anode rod.

My toilet valve froze last winter.  I didn't discover it for a while. There was just a tiny crack in the valve that sprayed a fine mist on out the back, which eventually trickled down into the shower basis. 

I do the antifreeze but apparently I wasn't diligent enough.  This the kind of thing that is much more likely to happen if you blow out the lines, in my opinion, anyway.

The repair to the toilet was surprisingly easy -- after removing the toilet, and only cost about $25 for a part on Amazon.  Still, $3 worth of pink stuff would have saved a lot of effort.

TT

Tom, north of 49 here. I do both air first then pink rv anti-freeze. It doesn't take a lot of time. When it gets down to -40c for a week at a time. That's why I do both. For the few extra minutes it takes to do both, I figure its worth it.

My 2 cents.  Did the antifreeze the first year in 2011.  Took a lot of time to rid tank, lines of that nasty taste as we use our FW for drinking.  Since then we have used compressed air, takes about 2 - 3 minutes to do the whole thing.  No problems to date.  Still will use about 1 pint of the pink stuff to put into the 3 traps (2 sinks, and 1 shower).