On the new Killer Endgame Dvds by GM Nick Pert he said, "It's not that easy!"
Roger S. said that one GM said these kinds of things happen so seldom that they aren't worth knowing. With 5 min. chess being very popular these days that is no longer true. And sometimes if you are desperate and have inferior material you might want to swap down to be the lone K against the "animals." You may draw because of the 50 move rule (no capture has been made nor pawn moved in the last 50 successive moves)!
Most endgame books do not have this info. Silman left it and the B+N out but so have others.
One book which does discuss it is Karsten Mueller's and Frank Lamprecht's Fundamental Chess Endings. They say the longest win is 19 moves (must be perfect moves!) Reuben Fine's Basic Chess Endings says 18 moves.
Gentlemens Chess Club member Mark M. managed to do it. First with cooperation from his opponent, on the side of the board, and then in the corner without the cooperation of his opponent. Congratulations Mark.
My advice sir, ignore the GMs, they aren't playing for you. And the ones who suggest it isn't worth learning probably know how to do it. Not too long ago I heard a story about some GM not being able to deliver the N+B mate in the required time.
I sell Karsten's book if you are interested, and I think we all should be.
PS: Bob's Birthday Bash is this Saturday at the Gentlemens Chess Club tournament, 1101 W. 4th, Davenport, IA. Starts at 10, EF is $25. Game in one. Four rounds.