That whole "lmao, lmfao, lol, rofl, etc" thing is true. People do that to seem like they don't care about the argument, and make the other party look like they care more, too much, or just makes the other party look angrier.
While what Taboo said in the thread was uncalled for, I wouldnt go so far as to call him heartless, insensitive, but not heartless.