It's not a novel concept. Bitcoin is a linear web of trust, applied to transactions instead of identities. Webs of trust are as old as PGP. Block C is valid against Block B is valid against Block A, which we both trust.
Bitcoin is respectable primarily for its ambition, the way it applied existing technology to accomplish a goal that its creators cared about and which many people would've thought was too daunting to undertake.
Believing that people only criticize bitcoin because their minds are too small to accept the concept of decentralized money is blatantly closed-minded.