Some Fellow AVs have some elements of Advanced Heuristics (we can say it's Behaviour Blocker) and Common Sense (smart HIPS). That's why we use Fellow AV and not rely only on Fellow Human (or Fellow Lynx ).
The same for Updates - smart Humans update their skills and knowledge like AVs their sigs and engines.
Well as my former High School Teacher said to us before, our brain contains 'Trillion of cells', so in that case; incremental updates is included however heuristics it downs only in instinct by reacting our emotions though.
Compatible to other Antivirus can be compare as a research reference for humans to improve more on heuristics and signatures.