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Bitcoin is designed to have an average time duration of 10 min between block mining. This is maintained by the difficulty attribute and haskey complexity. But mining takes so much power and it is a manual process as well.
Why it just not create a block every 10 min automatically?
Now bitcoin has 10kb(not sure exactly) reserved for priority transactions of pool. Let's just decide priority by the same functionality, and fill our block with transactions.
Users need only send transaction to the pool, no power lost and it is automated. Blocks will still have it's hash codes, and all immutability would be maintained. Just miner need not find it. Say I have coded bitcoin like this: 1. 5 min for every new block. 2. only one transaction from one public key at a time. It will stop the double spend, and no need of POW, and within 5 min, changes will be reflected in connecting nodes.
Why are such methods not used?? What are the drawbacks??