If you are cleaning house and want to delete programs you’ve watched, it’s puzzeling that if you have three shows to delete Tablo offers a singular “Delete.” But if you have only one show to delete, Tablo offers “Delete All.” Seems like it should just be the opposite. If you have three shows, it should offer to “Delete All” and if there is only one show, it should offer only “Delete.” Could this be reversed so it would offer you the correct choices?
Which device?
my controller is Roku but I think Tablo provides the recording and deleting schedule for programs Tablo is
set to record and play.
Using the web app (via Firefox in this illustration), I have 9 episodes with the option to Delete All 
Here I have a single episode, still have the option to delete all - 
I don’t have it marked, I believe there’s a post or tablo blog about how you can set to keep X and use some setting to mass delete almost everything… yet keep some. I don’t recall the specifics, or what you truly wanted, just rephrasing?
I do know there are 3rd party apps which allow selecting to delete and whole bunches of flexibility.