This long-overdue translation (by Rachel Barney, Toronto) of Aristotle’s seminal, On Trolling, is worth a careful read. A sample:
Hence the modes of trolling are many: the concern-troll, the one who ‘sees the other side’, the polite inquirer into the obvious. For the perfected troll has no need of rudeness or abuse, or even of fallacy (this belongs rather to sophistic or eristic, and requires making an argument): he only makes a suggestion or indication [semainein ˆ ].
Read it. It’s only two pages.