[Considering he still feels sort of wrung out from his earlier conversation, Crowley doesn't want to retread the same ground, so he just hums to show that he's heard and leaves it at that.

It's for the best, anyway, since everything that Martin says next leaves him a bit lost for words. First, he's just flustered and emotional, before it tips into faux indignation. Crowley makes a few useless sounds before he lands on actual words.] That was the fashion! Plenty of men were sporting those sorts of beards, how was I to know it'd seem ridiculous by today's standards.