not knowing how to take care of a pool?
Having grown up with a pool and being made to help take care of it, I know my father had no clue what CH, TA or CYA were. The only thing we did to maintain the pool was to throw in a cup of HTH chlorine every day (he bought it in very large drums) and add acid occasionally. I think the first year he may have tested for chlorine and pH, but other than that, we never owned a test kit. Brushing was unheard of except when algae was really bad.
My father in law has also had pools most of his life and he currently has a pool service company. It has lots of algae stains and the water is never perfect. After talking to the service guy, it was clear he had no clue and just throws in chlorine and acid and occasionally algaecide. Most of his time is spent vacuuming the pool and his test kit is a cheapo wal-mart one that tests for CL and pH only. HOWEVER, I can remember back before getting the service guy, my FIL would use a cheap test kit to check for Chlorine. He'd take the bottle, add a few drops directly to the pool, and if they briefly turned yellow, then all was OK.
And my neighbors were over swimming a couple weekends ago and commented on how nice our water was. I asked what they did to maintain their pool, and they said we use the "when green, add chlorine" method. What about pH and all the other parameters? They just looked at me funny like I was some alien. In the end, I think they convinced themselves that my pool water felt good because it has salt in it.
But I understand how people can be confused and mis-informed. My PB admitted that he has black algae in his own pool, but since he has a pebble tec finnish, its not noticable, so who cares? And even on the Taylor web site they recommend shocking weekly.