Re: Have I stolen this riff?
I don't think so. The first three chords of the progression seem familiar - a Lennon song? - but nowhere near as transparent as Fleetwood Mac's use of Capt Beefheart's Abba Zaba in Tusk or Cozy Powell using Jimi's Third Stone from the Sun in his Dance with the Devil.
And they got away with it.
I always though George was a bit unlucky with My Sweet Lord ... I didn't think it was a ripoff of She's So Fine at all, and was a much better song.
BTW, Help the Itchy is a killer song title. You and your sister are completely barmy ... just listening to Tea now ... a British Muffin Man :)