Trolling is when people post stuff they probabaly don't really give a toss about in the expectation and with the object of stirring up dissent. That's its "agenda".   

And it pretty clearly isn't the agenda in the case of this thread.

Whether on the Mudcat or in the real-world folk get togethers, it's much more fun when they operate in such a way that a range of different folk traditions, and a range of the various communities that have developed theser traditions, intermingle and interact. Trying to identify the factors that often stop that happening is a thoroughly worthwhile agenda.