Caleb did specifically mention to watch lowers on the TK cross as they are prone to balls sometimes. I would guess an OG x tk would bring that out more than say mendo p x TK or something along those lines. I grabbed some myself.I'm so stoked on his TK crosses. got a grip!
And i would have to agree i do think the lower population hunt of Chem 91 s1s probably isn't worth it and you better off running a hybrid. I personally haven't run the chem 91 gear so i should shut my mouth.
To touch on the Chem D.... the info gather is that Caleb a Chem D that is held really tight compared to some of the other chem d cuts that go around. Definitely prone for nanner and nanners in its progeny. it won't stop me from grabbing a pack of hybrids when he releases them. You know if he did Chem D s1s he has other strains he hit with it.