I would venture to bet may phenos similar to Chem D can be found in Chem 4 S1's and Chem 91 S1's if you were to unlock the treasure chest.
Regardless, Raindance is 75%+ Chemdog genetics and can throw all sorts of gnarly phenos. =)
Re: S1's, throwing other Chem phenos. Yeah that's likely (unless you're one of the people that think Chem D/Chem 4 are actually Chem91 hybrids, but I won't go there). S1ing them will throw a ton of interesting phenos, probably all chemmy as hell. I would absolutely run s1 lines of Chem91 if I ever got my hands on the cut.
However, when talking about F1s, all plants are going to be intermediate between the two parents. Some plants might lean more towards one parental pheno over another based on the dominance of genes it received, but I would never expect one parent or one grandparent to dominate any pheno. If you run enough seeds you could find a grandparent pheno in the F2, but it would mean running a LOT of seeds.
I believe the math at "S3" is either 97% or 99% identical expression. Someone check my math.
Not exactly, you really can't do math like that with S1s like you can with backcrosses. You could say that any S1 shares 100% of their genetics with the original clone...because all of it's genetics came from the clone. It only has the one parent. But is an S1 or S3 identical to the clone? Nope. All genes that are heterozygous (A1A2) in the original clone will continually be recombined (25% A1A1, 50% A1A2, 25% A2A2). If the original clone wasn't highly inbred (inbred lines have very low heterozygosity, so little recombining of genes), you'll always see some variation in the selfed generations, no matter how many generations you self. Careful selection of S1s for the original clone phenotype will lead to offspring more similar to the original clone, but if some of the phenotype is due to the heterozygosity, which is possible as not all genes show complete dominance/recessive relationships, it'll continue to show variability.