Last night I stayed up studying the Bishop and Knight forced checkmate. It isn't simple, but it is always possible. Against a strong opponent it is usually done in three steps:

1. Force the King into any corner using your King, Knight and Bishop.

2. If the opponent's King is not in a corner of the same colour as your Bishop then use your pieces to force the King into the corner of the same colour as your Bishop.

3. Use a simple set of moves to checkmate the opponent's King in this corner.

 Here is an example of this in action. The start position is with the opponent's King in the wrong colour corner. I choose to not illustrate step 1 in this example because it is easy compared to the rest.

Update: there were a few inaccuracies in the play of Black. Here is the updated version that is more accurate.