whatever-OPS
To shed some light on the confusion
JAA published JAR-OPS. JAA no longer exists
JAR-OPS was superceded by EU-OPS which is a European Commision thingy.
Now EASA is finalizing EASA-OPS which is planned to come in to force April 2012.
as mentioned some JAR-OPS rules still hang around, these are, as far as I know, JAR-OPS 3 (helicopters) and FCL which will directly transfer to EASA. Maintenance was allready transferred to EASA with the intruduction of Part-M before EU-OPS came in to force. Now I might be as confused as anybody else so I stand to be corrected.
I dont have a direct answer to the topic starter, but as far as I have read the new EASA proposals the rules regarding airplane performance and procedure design rules will largely remain unchanged.
Hope it helps, all the best