I can't find documentation about BIP 40 or BIP 41 anywhere on the web. The list of BIPs shows that they are by Marek Palatinus, but there are no links to them.
BIP 0040 is about the Stratum wire protocol, and BIP 0041 is about the Stratum mining protocol.
The stratum protocol existed for a while before BIP numbers were eventually assigned. Presumably there was some discussion that they should have BIPs and so BIP numbers were assigned. Stratum started as Electrum's protocol, but Slush realized that it could be used for mining, so the original protocol was extended. Thus two numbers were assigned, one for the original protocol, and another for the mining extensions.
Unfortunately, while the numbers were assigned, the documents themselves were not actually written. This was due to the authors not having enough spare time to do so, and presumably writing such documents was not a high priority. The BIPs remain unwritten to this day.