Notes, Notings, and Common Refrains

I couldn't give you a definitive answer because like most history it'll vary from time to time and place to place so the answer would be either "Dunno" or "Both" depending on which more specific question was being asked. The manufacturers of particular pieces of ecclesiastical glass, even the earliest, are fairly well recorded (although individual designers aren't so well documented) but masonry tends to be either the stomemasons of/from X OR George Gilbert Scott. [/ecclesiastical architecture in-joke]. I'd guess the answer would also depend on the visual prominence of a grotesque in its original setting, which is not necessarily the context its seen in now.

Interestingly, the earliest creatures I recall seeing in ecclesiastical contexts in England (i.e. Anglo-Saxon rather than Roman) have ALL been realistic depictions of wolves OR dragons (i.e. the pre-Christian Ang-Sax animals associated with destructive forces). Also, the most human-visaged and terrifying angel I recall was Anglo-Saxon. It was a true (don't) Blink angel. ::shiver::