Here's a simple derivation of B, C, and I from the pair {CCCCpqqrCCrsCps, Cpp}:
 
   

               1. CCCCpqqrCCrsCps
              2. Cpp                                         [I]
D1.1 =  3. CCCCpqCrqsCCrps
D1.2 = 4. CCCCpqqrCpr
D3.2 = 5. CCpqCCqrCpr               [B]
D3.4 = 6. CCpCqrCqCpr               [C]

And from here, two additional familiar formulas follow immediately:

D4.2 = 7. CpCCpqq                             [Pon]
D7.2 = 8. CCCppqq                             [Specialized Assertion]
 


Dolph Ulrich, 2007