AN,
I think thats flawed logic. Its about market value not appraised value. In some cases a house is worth more without a pool so removing it would add value.
Its also about what you pay for the house. The pool could be preventing the house from selling which is often the case in homes with small yards that are nearly all pool. If you can get it for a price that compensates you for the removal cost it could make sense. The numbers either make sense or they dont.