Sticky vs non-sticky sessions and the recommended configurations should be discussed in better detail the docs (it is not discussed at all for Tomcat module). If the user configured client-server topology with non-sticky sessions, we do NOT recommend enableLocalCaching be set because it results in unpredictable asynchronous behavior/replication.
If they follow our recommendations and disable local caching (proxy-only client), then they should also set `gemfire.EXPIRE_SENDS_ENTRY_AS_CALLBACK`. Otherwise the expire logic will not be called on the client. The side effects of this may be benign, but if there are any listeners depending on that expiration logic, it may result in bugs or a resource leak.