Real men create wealth, leaches take it.
After using it for a few years, especially in the heat of takeover battles and the like, he renamed it "The Semi-Defensible".
Characteristically - and I think this is a big reason he's so wealthy - he spotted the "Indefensible" as a business opportunity. Since he doesn't use his jet 24/7, most of the time it's parked on the ground. He figured out pretty quick that he could let other people use it while he didn't need it. That led to him buying out Executive Jet, a bizjet timesharing firm, which I believe is now a solidly profitable part of his little empire.
So he made a nice profit out of his one indulgence. Gotta admire him for that.
D