Aside from the tapes and Gravano, did they have anything or anyone else to testify against him? He went to the apartment because he knew the ravenite was bugged. Wouldn't common sense tell you to be a little more precautious. Like everything else with these guys, who knows what it's like to be in their shoes. Maybe he had a mole that told him that they had only the ravenite bugs giving Gotti a sense of security.
It was no coincidence that those tapes were recorded in the winter. Normally Gotti went on walk-talks if he wanted to discuss something important, but the cold on those days was too uncomfortable for him I reckon. He also should've put a guard in the appartement when Mrs. Cirelli went on her vacation..
But at the end of the day it's like you said, it's easy to criticize the man but we never walked a mile in his shoes..
