Moffat was reflecting on the 14th anniversary of that frightening tale airing on BBC One, starring Academy Award nominee Carey Mulligan and Unforgotten star Finlay Roberton as unlikely partners Sally Sparrow and Larry Nightingale.
Together, they must unravel a confusing set of clues left behind by the Doctor (David Tennant) and his companion Martha Jones (Freema Agyeman), who have been sent to the distant past by the Weeping Angels.
The Doctor himself has a small role in Blink, to such an extent that the episode was filmed simultaneously with another chapter from the third series, which might be why Tennant was seemingly not present for the read-through.
In an Instagram post, Moffat recalled: "Brand new, exclusive fact (unless I’ve revealed it before which is more than likely.) At the Blink readthrough I read the part of the Doctor. I was GREAT! People wept.
"Russell [T Davies] slapped me. I’m sure he meant it as a compliment. As a direct consequence of that readthrough, Carey Mulligan became an international star. And I moved on to doing the stage directions."
Earlier this year, Mulligan earned an Oscar nod for her powerhouse performance in Emerald Fennell's darkly comedic thriller Promising Young Woman.
Moffat went on to take over Doctor Who after Davies' tenure on the show ended, overseeing the distinct eras starring Matt Smith and Peter Capaldi before handing the reins to current boss Chris Chibnall.
However, he has remained a big voice in the fan community and some may well be intrigued to know exactly what his take on the Doctor sounds like. Sadly, no recording of the session has been shared (yet).