Somewhere, I read that NOEL HILL instructs english concertinists in his workshops to execute ornamentation on the same side as the note being ornamented.
now there isnt JUST one correct way to do ANYTHING, but I would do the oppOsite and cut on the oppOsite side of the ornamented note,.
because of the nature of the instrument, english players tend to develop good coordination between left and right, anglo players have not necessarily, through the nature of the instrument, developed this skill.,to such a degree.
In other words, because they dont play the instrument they dont understand what comes naturally to the english concertinist, and instruct from the point of view of what comes naturally to the anglo player,.I am sure this wouldnt happen at Witney, and Iam sure this is not the advice in Alistair Andersons tutor. The only time I execute ornamentation ON THE SAME SIDE is perhaps when the note after the ornamented one is on the opposite side. a G on the left followed by an A on the right, I might play a cross fingered triplet for the G. Dick Miles.