The most common and most likely answer to this crossword clue is the 1 plus 3 plus 2 plus 4 letter word I HAD NO IDEA
I've seen this crossword clue in The Guardian
I
H
A
D
N
O
I
D
E
A
Buddy explains!
The straight part
We know that "This writer lacked a single bit of inspiration/You surprise me" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case this writer lacked a single bit of inspiration/you surprise me = i had no idea.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.