This was terrifyingly hard not to do. It was drummed into me that jargon or slang must be enclosed in quotes, because it was incorrect English.
Also, a lot of the books I read (school stories for example) do exactly that, and we all know how influential the media is on impressionable minds, eh, chums?
Except it looks horrible, is scholarly-pompous and slows you down as a reader.
I was certainly strongly aware I was doing it (witness the joke on AP43's disk pages) but couldn't break the habit until almost a year later, when I sat down to write something and found I no longer wished to use a device redundant since 1941.
Phew.
And anyway, it was never quite as annoying as desperately overusing capital letters.