I'm not yet used to all the different patterns for getting notes out on the triple row. There's more options than a single row and I'm not yet where I can hear positions when someone is playing a triple row, unlike on a single row (sometimes).
i think we used to do that in C on the F row [2nd position]
but i have never heard chubby;s version
it was just where the guitarist wanted to sing it, or it was a compromise between his voice and available accordion keys i had at the time, and his guitar solos