No sense or No logic to restrict Option buying with pledged share margin

No. Where has SEBI said that? Have you ever read an option contract?

To understand how credit and debit works on a position you may have to try another broker. I use a different trade account and let me try to explain.

If I take a credit spread with a max profit of 6000 for a max loss of 4000. Then the broker credits me Rs6000 same day. If on expiry my trade is on max loss then I need to maintain 6k+4k in ledger and it will get debited.

What this means is that money flows from the person on the other side of the trade to mine on the trade initiation day. That’s why he cannot use collateral and I can.

Everyone has their own strategy. My question was more about choice rather than strategy.