Board Thread:What If?/@comment-5674726-20141111204657/@comment-5674726-20141116184415

Machairodus wrote: Merlin's abilities are defined by the plot convenience. It could be that the writers were simply doing what they wanted(and probably, sometimes they were), but I don't think so.

I think that this was a case of a couple of tropes in action: New Powers As The Plot Demands and Early Installment Weirdness. Rather than let Arthur save himself, they had to have Merlin be the one to guide him out of the cave and, given that it was very early in the series, I'd say that they were also playing around with different ideas and that this one that Merlin has a sixth sense for when Arthur is in danger and some kind of telepathic link to him was quickly abandoned.