Water pressure fluctuations can do strange things; even make water travel uphill; even back up the hose bib by just shutting off or opening a valve somewhere else in the house (that is why they make back flow preventer's).
If opening the faucets to drain your hot water heater makes you happy; who am I to say you can't.
Just saying, I wouldn't.
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW