any information on this?

I am pretty bad at endings for my rating, but I think this is one of those scenarios where it takes the stronger side like 200 moves to win with perfect play.  I am pretty sure this would be a draw if any humans played.

I think it's theoretically drawn but I don't know much about it specifically.

I generally agree with Sarthe on all his points except 2 knights usually cannot force a draw and queen versus rook usually can, although tricky against perfect play.  I failed repeatedly against computer.

If you give a queen 10 points (as some books do) and knights just under 2.5 (no book I know of does, but 2.5 is common), the rule holds except, as Sarthe mentions, in extraordinary situations. 

Here's a link to an awesome endgame tablebase server. Play around with it.

http://www.k4it.de/index.php?topic=egtb&lang=en

R + B vs R is a draw in the vast majority of positions, yet there are some very unobvious postions that are lost for the lone rook. It's computer chess/GM chess stuff. Call it a draw if you're not a professional!

Here's one to ponder: (ooops, I goofed -- this puzzle diagram was supposed to explain at the very start that it's Mate in 33! -- I am asking you to take your best guess at finding the first move -- there's only one! All others draw.)

Philidors classical position for Rook and Bishop and King vs Rook & King demonstrating the correct technique to win this rare checkmate it's easy for the defender to make mistake because mate is threatened on all sides the only way to delay the mate is to sacrifice the Rook Rxe5+ after move 11.

    Why not 7...rf3 in the philidor position? [edit] ah... got it.. Bd6+ Ke8 Rg8+ Rf8 Rxf#8

Thanks for posting that ending Alec -- very instructive... that start position can't normally be forced though.

JG27Pyth

I guessed your puzzle correctly but it was indeed a guess so it is a hollow brag.  Can you elaborate on the position?

JG27Pyth wrote:

http://www.k4it.de/index.php?topic=egtb&lang=en

Yeah, but this is just taken from the shredderchess website:

shredderchess

Escapest_Pawn wrote:

JG27Pyth

I guessed your puzzle correctly but it was indeed a guess so it is a hollow brag.  Can you elaborate on the position?

It's mate in 33 and over my head. Just something I stumbled on playing around with the endgame tablebase. Click on the link (or the link in the message below labelled "Shredder"), put the position in the diagram, wait 10 seconds or so, the tablebases will load up for you and will show you how to proceed in that diagram or any other ending with 6 total pieces or less (including Kings  --  and  not  with  5 pieces vs the lone K which are too easy to bother with).

Thank you.

There is a post by some WGM on this ending...

Rook and Bishop vs Rook is draw if played correctly.

With so few pieces, it's easy to check out on the Nalimov tablebase.

http://www.k4it.de/index.php?topic=egtb&lang=en

It seems it's a draw, mostly, with a win in some special cases. The longest forced win position I could find was a mate in 22 in thi position:

On move 91 Karpov demonstrates the Second Rank Defense  SRD.  (In this case it would actually be the Queen Knight file defense)  Karpov's King has been pushed to the near-edge.  The key point to this defense is that the stalemate trick prevents the attacker's king from joining the mating net.