Runners that are farmers also have pathing issues and are more likly to get stuck and lose what they are carring. Like the kids that get stuck on huts or rocks do. Be prepared to lose at least 5 baskets of veges every harvest due to this. I haven't seen lost fish though but I can't say I watch them that often. If you use the harvest trick where everybody picks veges when you only have 2-9 left keep an eye on the runners for the "lost" baskets so you can drop them back in time. They do harvest faster then the others do.