Might Cardano ever consider masternodes for instant transactions?

It seems like at some point in the future this might be an appealing option. I know Cardano is focused on security vs high tps but it would be practical to have dual options. Or would this make matters too complicated ? DASH has this feature and was cited by Hoshkins as a good one.

Cardano will have offchain transactions, that will be instant. (i.e. individuals swapping private keys on trusted hardware)