There's way too much patronizing here for my particular taste. I don't understand all these opinions, without mentioning a single fact. Why don't we just read (or read again) what the Master said?.
http://reefkeeping.com/issues/2005-10/rhf/index.php
In my experience. I have a 100G with 3 fishes: one Yellow Tang, One tomato and one mean SOB yellowtail, also one peppermint and 40 in snails, red and blue legs. And a few purple mushrooms. I love them all.
A couple of years ago I went through a nasty divorce, lots of personal problems, illness and whatnot. WC were after last in the list of things to do. The tank went months without WC. The skimmer was working. Feeding was sporadic (couple of times a week) and no dosing anything. Half of the lights (VHO) were gone.
I didn't lose a fish. The mushrooms were growing and everything was just getting by. Nobody died. No algae (no super powerful lights) blooms, no red slime, nothing.
I just restarted the tank because I couldn't get the nitrates to go down and I wanted to add more livestock and the tank look nicer.
When I recovered I emptied the tank. bleached the rocks, got rid of the sand. Bought new LR, a MH fixture and a GFO reactor. Fixed the skimmer and i'm dosing ca, alk and mg.
Coralline is thriving and everything looks good (maybe the lights) but without a WC in 2 years the tank was just OK.
What I don't like is people here with "your join date is XXXX" (you know RC is not the center of the universe), "I'll buy your tank in craiglist" and all these reactions to people that are only exposing here their experiences without WC.
Summary: if you are not helping, you are a PIA.