From what I understand, in today’s environment, ASIC miners only solve the math to allow for the assembled block to be added to the chain. It is the pool (not the pool of hashers but the devs of the pool itself) that actually assemble a block. These ‘pools’ only assemble but do not hash. It is the miners in the pool that actually do the hashing. Is this correct?
1 Answer
I believe that for many pools, the pool operator creates the block template for which the miners who are pool members attempt to find a nonce and other block data that cause the block's hash to be less than the network target.
The pool members also report back any blocks they find that have a hash less than an easier pool target - and this is what is used to measure contributed hashpower.
It may be that some pool protocols also give pool members some ability to select which transactions are included. But I'd guess the coinbase transaction is always specified by the pool operator.
So I believe, in brief
pool members contribute hashpower and do all the hashing.
pool operators coordinate activities, ensure members contributions meet pool rules, measure hashpower contributed by each member and apportion rewards accordingly.
I would expect pool protocols to allow the pool operation to be transparent so that pool members are able to verify contributed hashrate etc and hence verify that the operator is operating honestly.