I actually considered allowing them to jump down cliffs. It'd be interesting, but right now their wallchecking is using a default onwallpath() function. If I allow them to jump down cliffs they'd have to be able to look at players over cliffs, which means a custom wall check. Not hard, but it will be more taxing than using the client function. For a feature that will be hardly used, I don't think it's worth the extra processing/effort.

Also their chase distance is fairly large, but if they can't get to you(because of a wall) they will give up.