is the skiplist as described in the SC WP the same as SCIP? doesn't sound like it.
Right they are different things.
SCIP is the underpinning of SNARK though.
SNARKs. An exciting recent development in academic cryptography has been the invention
of SNARKs [BSCG+13]. SNARKs are space-efficient, quickly verifiable zero-knowledge
cryptographic proofs that some computation was done. However, their use is currently
inhibited because the proofs for most programs are too slow to generate on todays computers,
and the existing constructions require a trusted setup, meaning that the creator of the system
is able to create false proofs.
A futuristic idea for a low-value or experimental sidechain is to invoke a trusted authority,
whose only job is to execute a trusted setup for a SNARK scheme. Then blocks could be
constructed which prove their changes to the unspent-output set, but do so in zero-knowledge
in the actual transactions. They could even commit to the full verification of all previous
blocks, allowing new users to get up to speed by verifying only the single latest block. These
proofs could also replace the DMMSes used to move coins from another chain by proving
that the sending chain is valid according to some rules previously defined.
...
[BSCG+13]
E. Ben-Sasson, A. Chiesa, D. Genkin, E. Tromer, and M. Virza, SNARKs for C:
Verifying program executions succinctly and in zero knowledge, Cryptology ePrint
Archive, Report 2013/507, 2013,
http://eprint.iacr.org/2013/507.