I work them through that by myself regularly, not sure why you need an extra person.Well if it works for you. For me it would be an interruption in the flow and take an extra person. Zero need for it here.
The slide gates prevent having more people. One person can move them beginning to end with out getting in or stirring them up.
Cows are smarter than people give them credit. I have seen a cow give my son or a friend problems, but when I get in with he she goes right where she is supposed to. The test people just like equipment.