Sorry about the lag! I've missed this comment. Yes, although the docs are ambiguous, performance does improve with that limit (in live tests). Plus, found this in Apple docs:

"If you are using the SQLite store, you can use a fetch limit to minimize the working set of managed objects in memory, and so improve the performance of your application."

Ref.: https://developer.apple.com/library/mac/documentation/cocoa/conceptual/coredata/articles/cdPerformance.html