interesting, going on those numbers it sounds like a pretty simple situation with regards to inheritance then. because that sounds a lot like the ratios you'd expect if it's just 1 recessive gene(15-20% in f2 is close to 1:3, 40% in f1bc1 is close to 1:1).
and then those f2's with only slightly altered leaves could be either heterozygotes expressing the trait very slightly, or maybe in some cases it is homozygous freakshow-leaf but some other gene hides the expression or something like that(incomplete penetrance).
and then those f2's with only slightly altered leaves could be either heterozygotes expressing the trait very slightly, or maybe in some cases it is homozygous freakshow-leaf but some other gene hides the expression or something like that(incomplete penetrance).