You can do a lot in script, but if all your routing logic is in a long/complex scheduler/netwatch script, it quickly becomes an ugly hack and difficult to maintain. I think @msatter’s [PROPOSAL] Event driven scripting deserves some consideration. If scripts to control routing were more tied to “events” (change in config/counters/snmp/routes/etc)… it be WAY less of a “hack” and cleaner to apply heuristic-based routing on top of existing protocols (and, eventual, IS-IS).