TWO ROW MELODEONS were introduced relatively recently during the the uk folk revival
Peter Kennedy got the first D/G instruments manufactured for the English folk market - a batch of Club Models built by Hagstrom, a Swedish firm who had set up an accordion factory in Sunderland after WWII and brought Nils Nielsen with them as a young factory-trained tuner. Those boxes were made (subject to a Licence from the Board of Trade, in those immediate post-war years of restrictions, rationing and 100% Sales Tax on musical instruments!) especially for the English Folk Dance Society in 1949, and they could only be bought at that time by members of the Society who had pre-ordered them.
Why should fiddle players be imitating a relatively new instrument, that has a short history as a traditional instrument and bears no resemblance stylistically to a fiddle[ one is a fixed note instrument] that cannot play anything other than semitones and is unable to play quarter tones or any notes between quarter and semi tones. I find the idea of fiddles copying melodeons, illogical .
Logically a fiddle copying a melodeon is about as appropriate as a fiddle copying a Hammered Dulcimer.
Musical styles will continue to cross geographical bundaries ,my advice to all musicians is to listen to styles from many different places and develop ones own style
Jons opinion on english fiddle development is in my opinion,of little merit.Dick Miles