Water tank draining

Since 2012 this is the method I have used: As lostagain (Fred) wisely advises, turn off your water pump and turn hot and cold water on, this will release any pressure in your lines.  Access the 3 way valves and turn all 3 to winterization mode.  Drain HW tank.  Take a air hose (I limit it to 90 psi) and have a line open, connect air hose to pigtail under sink and open the valve downstream from the pigtail you connected to (about 12 inches away) turn air on and one by one open taps one by one until nothing but air comes out, always have one open before closing the former, this process takes maybe 90 seconds on our 177 and that is going through each tap 2 for the kitchen sink, 2 for the bathroom sink, and the one for the toilet flush twice each.  Turn air off and close the 3 way valve. Turn off last valve you left open.  In the past I would check my low point drains for water but after 3 years of doing this and maybe finding a drop or two in each I haven't even checked them for the past 5 years and have had no leaks.  I then take 16 oz. of RV anti-freeze and pour almost 5 oz. into each of the 3 traps and leave about 1 oz to put on top of the toilet flapper to keep the seal moist during the winter.  Entire process takes about 15 minutes from start to finish.  

I think there is some call on where you live, I don't use AF, but if I lived in the East or North I would certainly consider. I use pressure air and have never had anything freeze, course always a chance. If that chance happened I'd adjust.