Mass Super skunk = sensi seeds super skunk (Super sick phenotype, just like how the Cheese is a sick pheno from a pack of sensi seeds Skunk #1).
Chemdog 91 is the original choice selection from 13 seeds found in the legendary bag of dank from the greatful dead show. Chemdog 91 is the source of most OG Kushes and OG hybrids.
The original O.G. Kush (ocean grown kush) is an S1 (selfed feminized) seed from a bag of Chemdog 91.
Chemdawg D was one of four seeds of that original 13 which the chemdog 91 was discovered from. It was popped years after 1991.
Diesel is I believe just Chemdog 91 renamed by JJNYC of TOPDAWG seeds. (I may be wrong about this). It might be Chemdog 91 x and afgani or Northern Lights, but again, I'm not sure about that.
Sour Diesel has different opinions on its origins. For instance I have read that AJ's cut of Sour diesel was his first Sour diesel to come out of his Sour Diesel project room. It was this Sour Diesel that is supposed to be the pre-cursor to the East Coast Sour Diesel (ECSD).
I believe the ECSD consists of Chemdog 91 x mass Super Skunk x NL (or NL #5xhaze, or an Afgani...not sure exactly).
The clone only cuts from these chem family are:
Chemdog 91'
Chemdawg D
MassSuperSkunk
AJ's Sour Diesel
ECSD
Chemdog 91 is one of the best (if not the best) smelling, the best tasting, and one of the most potent strains I have ever experienced in over 20 years of 'puffin tuff'. It is agreed upon many Americans and by people overseas that chemdog 91 (the real deal) is probably the best weed in the world known today. Truly legendary shit.