Sounds like a good idea. So these mini-blocks would only contain the time, the previous block hash, and the nonce? Would they also contain the previous mini-block hash or just the previous normal block hash? I am assuming that you would expect miners to choose the chain with the most mini-blocks in the case of a fork? That makes a lot of sense.
The proposal here is to just use it to determine total network power.
In
my thread (referenced in the OP, but not linked), the proposal was to have miners count the number of mini-blocks confirming each full block and then use that to break ties. This would move the majority of the network hashing power onto a single block much faster than the current system (when 2 blocks are found at around the same time).
The current system waits until the next block happens before breaking the tie.