So maybe I'm missing something...
I open up a given play list, select a bunch of tunes and hit delete.
First of all, it prompts me that I can't delete songs from the player unless I am viewing the "all tracks". So I had to dig thru "all tracks" to locate all the tunes, instead of just a select-all from within a playlist.
Second, it prompted me with the same question for every single song I had choosen ( all 55 of them ).
How about a separate "delete from this playlist" and "delete from player" . You could even do a cross-ref and show us which playlists the file is a part of before deleting.