laanwj on Nostr: both are useful the block hash proves knowledge of some information that couldn't ...
both are useful
the block hash proves knowledge of some information that couldn't have been available before (same as using a newspaper headline, for example), so it puts a >= bound on the timestamp
OTS stamping can be used to prove that information already existed at a certain time (by putting it in a merkle tree that will be published in a block), so puts a <= bound on the timestamp
together these can "box in" the timestamp of the event
the block hash proves knowledge of some information that couldn't have been available before (same as using a newspaper headline, for example), so it puts a >= bound on the timestamp
OTS stamping can be used to prove that information already existed at a certain time (by putting it in a merkle tree that will be published in a block), so puts a <= bound on the timestamp
together these can "box in" the timestamp of the event