That song is on my short list for two of the most inane lines ever:
"If I was a sculptor, but then again, no"
WTF? Then again, NO? Didn't you proofread this song before you published it?
"You see I've forgotten if they're green or they're blue"
The things you do are green or blue?? WTF does that mean?
Might as well be Jabberwocky, except that was INTENDED to be doggerel, and humorously silly.
That line doesn't refer to a thing, but rather the color of his lover's eyes. Apparently, Reggie too was busy admiring some other trait to notice something as trivial as the eye color of his true love.