There is a scottish fiddle,bowing technique,where two minims that are tied, are played with one bow, but an emphasis is put on the beginning of the third beat;with an extra pull with the wrist.
this is a very good exercise for the english concertina,start off playing a major scale each note lasting four beats, without changing direction but giving an extra pull in the same direction on the third beat. Then repeat this exercise on a push note. I advise starting on a major scale[ c is an easy one or g]then try it on the mixolydian scale in g [ g a b c d e f nat g]or G DORIAN[ G A BFLAT C D E F NAT G ]. Dick Miles