Regarding 26a, thanks for the explanation of the last 3 letters (I was puzzled by this too). However, I'm still confused by the first part of the clue. If it's a definition of 'playing for time' surely that has two Ls in it?! Otherwise it means something else. So, where is the indication that one of the Ls is taken away? No-one else has mentioned this, so I must be missing something.
I can also only partially parse 3d. Where does the final VE come from? Or does the E come from ME (for Everyman, rather I), with comedy being Co, not Com, in which case where does the extra I come from?! And that still doesn't account for the V either. I would also quibble with the definition for this answer.
Other than those two, I enjoyed this offering very much though. Had never heard of the two scientists in 8d, but I guessed the answer from the definition and crossers, and now I know who they are, I like this clue! Also enjoyed 5, 7 and 20.