This is, after all, the "classic" thread-- so, I guess since your concerns are so sincere and neutral I should be expecting to see you open an issue on the classic github to tell them that disabling validation on blocks claimed to be a day old is bad and they should undo it?


Nice ninja edit there.  No-- Classic turns off validation based on a timestamp set by the miners. Core and every other full node other there skip signature checking on blocks below a hardcoded block 100,000 deep in the chain (a behavior, added by Gavin in 2011, which-- incidentally-- i argued against, but is now one of the things keeping the initial sync time tolerable on low power devices).  In any case, your dispute there is with every existing full node software, not Core. (And at least in core you can disable that behavior by setting checkpoints=0).  

I hope you can see the difference between not checking things in a chain with months of POW on top of it vs not checking when miners simply say so in block headers.