ASK NOT for whom the tweets troll, JP Morgan – they troll for thee. The bank, which was one of the underwriters on last week’s Twitter float, threw senior investment banker Jimmy Lee to the snarks overnight on Wednesday by inviting students to quiz him on “leadership and life” using the hashtag #askJPM.“What’s your favourite type of whale?” was one of the few responses printable in a family newspaper, referring to the multi-billion dollar London Whale trading losses at the bank.Another asked the firm: “Is it true that, while you don’t always spit on poor people, when you do, you have perfect aim?”“Bad idea. Back to the drawing board,” was JP Morgan’s sheepish response yesterday after calling the whole thing off.Thus learning a valuable lesson about the Twittersphere: engage in the conversation properly, and if it all goes wrong, put on a silly hat. It worked for Michael O’Leary, anyway.