Just in case there are any new growers in here that are getting confused...
Monitor your pH, period. If it is not in the desired range, adjust it. If you use tap water, that's okay, just do your best to let it sit in an open container for 24 hrs to de-clorinate. If you aerate your water, your pH will be less prone to drift while in a reservoir.
The statements above are not based on opinion any more than whether or not the earth is round or flat, without regard to whether someone wants to theorize that the world is actually flat.
I have seen a couple instances where very sophisticated growers, using TLO, have pushed through grows where they could not get their pH within normal ranges, yet managed to have stellar results. So, if the "pH isn't for everybody crowd" wants to hang their hat on that... feel free to take that long reach.
But, if you're not a sophisticated enough grower to make your own "super soil", pH monitoring and adjustment, is the most basic, essential aspect of high performance growing.
Sorry, but this debate is old and tired.