Sounds good, Simon!
Simon wrote: "Perhaps there were other variations that were added ad hoc by the improvising musicians during an evening's festivities where, for example a fiddler would say, 'here's another fragment of an Italian-sounding tune I half remember'? Perhaps the other musician would join in for the second or third time through."
Lol that brings back memories! Not specific to this tune, or Italian tunes necessarily, but all sorts of stuff.