Deletion of viewed streaming episodes?

Apologies if this has been discussed elsewhere.... Set up a 1P with recording and streaming, new and repeats. I was under the impression that after viewing a streamed episode I could "delete" it from the folder thus keeping track of where I am in my viewing history of a particular program. Kinda tough to remember what episodes I've already viewed if they all keep showing up in the folder. Do I not have it set up properly or is this normal behavior?