I once read in a Consumer Reports 1978 Buying Guide Issue on their built-in dishwasher ratings, of a few GE built-in dishwashers and maybe a few other brands, one of their disadvantages said, "Pits can pass into trap in pump system; trap must be opened from underneath washer for cleaning"-I never did understand what that meant, has anyone out there with an older GE or other built-in dishwasher experienced this kind of a problem?