stretching and nodal spacing has more to do with lighting and environment. Don't really have another answer. Well, I am sure Robert didn't change anything to make this an effect of ILGM genetics.
I would think that may be the strain itself. All genetics grow differently. Even the same strain, especially if strain is a "hybrid". Sometimes you get an Indica dominant pheno, Other times a Sativa dominant pheno. Indica is short and tight. Sativa can be tall and nodal spacing to be father apart.