The Rev Dodgson said:

Bubblecar said:

The Rev Dodgson said:

A mere 675 seconds, to be precise.

Yes, it did require a bit of working out :)

Thanks to dv for a teaser that actually needed some thinking about :) (the New Scientist ones have been way to easy recently).

I composed this one myself so I’m just glad I didn’t mess it up.

To run through the whole deal.

After Amy’s answer, we can eliminate all except those that contain a unique letter: PALS, SCAM, BAIT, AXES, FAKE, RIGS, LASH. Call this subsetA.

Bob’s answer tells us that his letter must be unique in subsetA. The possible permutations are
MC (SCAM)
BT (BAIT)
GR (RIGS)
KF (FAKE)

Before considering Carol’s answer, the permutations of the first three letters so far would be:
MCS
MCA
BTA
BTI
GRS
GRI
KFA
KFE

Of these, Carol’s answer only lets us eliminate KFE. Shr holds A, S or I but can’t narrow it down to one word.

So the four letters as called are among the following:
MCSA
MCAS
BTAI
BTIA
GRSI
GRIS
KFAE
Doug holds A, S, I or E but only the E would allow him to solve, and so the word was FAKE.