Guardian Genius 203

[LeenaH]

Please help with 12a
Singer - songwriter's number one impressing street(4)
-a-g
This is one of 12 themed questions.
Not sure about my crossers
Thanks in advance

[kettledrum]

What is the theme?

[iminoz]

(K.D.) LANG

[JJ109]

NB the wordplay comes from 10a

@Kettledrum
Twelve thematic solutions are to be entered in the grid incompletely. Their clues contain a definition of the full solution and wordplay for a different thematic entry in the grid. Wordplay for each of the remaining 23 clues contains a superfluous letter. These letters in clue order give a four-word indication of what the thematic entries are lacking. By a process of elimination, you must deduce the final thematic entry at 29 across, which (similarly completed) you might say is surprising.

[kettledrum]

Thanks jj. As iminoz had already answered I’d rather put it out of my mind. But the preamble intrigues me & I might give it a go.

[JJ109]

Do that Kettledrum, it really is an excellent crossword, I thoroughly enjoyed it!