The period we have a reasonable amount of bawdy material available to study runs from the 17th century onwards. Obviously the nearer we get to our own time the more material has been preserved, but what material survives would suggest that the nature of the material has not changed significantly during that 4 centuries as one would expect with material that by its very nature has been kept under wraps until c1950

'overlapping sets of song-types'. I presume here you are referring to origins and influences, as the only other way I know of classifying chanties is by their rhythm/tasks.

I only mentioned forebitters as something that would have definitely contained bawdy material. I'm acutely aware that chanties are very different in nature.

Regarding your assessment, you can really only go by the few first-hand accounts that you have given above, and these overwhelmingly point to the preponderance of bawdy inclusion. The fact that very little has survived as direct evidence is just unfortunate. By the time collectors came along who could get the singers to sing the real maccoy the day of the chantey was long gone.

I recorded an old Cape Horner in the 60s and whilst he sang chanties for real the versions he sang were standards and contained no bawdy at all. If they had he would have sung them, as when I first met him we were all singing plenty of bawdy material together in the pub but not chanties.

I'm not convinced that Stan's so-called bawdy repertoire actually consisted of chanties that had been sung by the real chantymen when chanties were at their height. I've no doubt that Stan had a healthy bawdy repertoire like the rest of us, but even in his young days the real singing of chanties was much influenced by what had been published.