Great though AB is, it is a public forum and you will never be able to stop Mamjet, and his sort, playing their games.
In an ideal world we would be able to say to the likes of Mamjet, "Stop what you do, because you are upsetting people". (Although in reality, I wonder if he makes a lot more people smile than he upsets - there are plenty of ABers who find his sense of humour very entertaining).
Unfortunately we do not live in an ideal world, so the only way to go, as said before, is to totally ignore his input if it upsets you. The more posters you get on here voicing their disproval, the more Mamjet will continue with his/her wind-ups.
And sorry but I have to say it - people who post on here for the first time, asking a geniune question, then getting a wind-up answer and becoming upset - really do need to become a bit more internet-savvy. You post a question on a public forum - you open yourself up to replies from all and sundry, including crackpots. It's a shame if people don't realise this until they receive an unwanted reply. But once you have been upset by an unwanted reply, you quickly learn what you might expect when posting your problems on open forums.
As mentioned before, anyone too sensitive to handle wind-ups would be better turning to a more reliable source of help. Internet question and answer sites are never going to be 100 per cent wind-up proof!
Banning Mamjet (even if we could) is not the answer. Another "Mamjet" would quickly pop up in his place, human nature being as it is. So why don't we all agree to take him with a pinch of salt. Stop discussing him and don't retaliate when he chips in with his witty/humorous/sarcastic/disgusting/whatever way you wish to perceive them, replies. He will soon get fed up and move onto another site when he stops getting attention.