While this is a pretty looking Early Girl plant on a nice trellis, complete with drip irrigation and Florida Weave string strands holding up the plant, it is really hard to see what Chuck means about pruning lateral branches away selectively and keep an occasional terminal bud branch to fill out the plant. Other viewers commented that it was hard to see, and Chuck said he was planning to get it re-shot with more close-ups.
Chuck is a great character, originally from Chicago, Illinois and now resident on a ranch in Orland, California. He refers to a “hand of tomatoes” (the bunch of tomatoes on a vine) and also about “fruit set” which is what you are trying to encourage through pruning. His next video on the subject will hopefully be more revealing.