Lightning is not a netting system, -- as a clear evidence for that netting universally involves counterparty risk of loss and lightning does not. But if you wanted to talk in terms of netting you perhaps should have said that.
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And in Lightning, unlike the check, the risk is eliminated because of Bitcoin magic.
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Lightning [...] without a counterparty risk for funds loss, [...]
This is not true. There is counter party risk when dealing with lightning. It is possible that your counter party could broadcast an old/"revoked" transaction that results in you receiving less BTC then what you most recently agreed to. It is not a guarantee that you will see such revoked transaction prior to the "lock" expiring, making the "penalty" transaction moot, and it is not a guarantee that you will be able to get the "penalty" transaction to confirm even if you do see the revoked transaction.
Also if the current state your agreement with your counter party is that you are to be refunded 0.0 BTC then broadcasting an expired refund transaction would be risk fee, and EV positive because even if you fail to be able to steal BTC 99% of the time, you would lose nothing 99% of the time and gain some amount 1% of the time when this is attempted, and the (psyudo)anonymous nature of Bitcoin will allow an attacker to attempt this attack multiple times.