Cheers, Suibhne. Strict parallel fifths are sounding good to me, even if after a while it starts to sound a bit stilted and faux-medieval - but is that necessarily a bad thing? I really am not the woodworker for the DIY hurdy-gurdy, though.

Will - The question is whether these parallel lines fit the underlying harmonic structure of the melody.

Slow down a bit - what is the harmonic structure of a tune, & how would I find out what it is? I've started getting into modes as a result of playing around with drones - I've had to: you can't tell from the key signature alone whether the drone that will work is (say) C/G, G/D or A/E. Haven't really got residency in Chordsville yet, though.