Hash chaining over logs predates the blockchain by a fair whack of time. If you don't mind a trusted authority cross-signing, it's a lot easier and a lot faster

Hash chaining over logs predates the blockchain by a fair whack of time. If you don't mind a trusted authority cross-signing, it's a lot easier and a lot faster. You don't need the batching mechanism quite so badly and ACID databases have a pretty good track record at establishing a trustworthy ordering of events.