This creates two classes of users and significantly reduces the percentage of the money supply used to secure the network.
Why? Here we see no explanation but just a statement of "fact" (or in other words "bullshit").
Additionally both of these systems suffer from the potential that a large stake holder could perform a denial of service attack by refusing to include some or all transactions.
They seem to have overlooked the "penalty" for not forging here.
you mis attributed some quotes to me. Ive fixed them in this post, please fix in yours..
but a forger could accomplish the same thing by choosing to forge empty blocks; thus avoiding the penalty. Its a fairly weak criticism, IMO.
But the criticism on only a few accounts being used to secure the network; is that valid? Is it necessarily a bad thing for say only 100 accounts to be active forging 100% of the time, where those 100 accounts have, lets say 15% of all NXT? Is that bad? If so, how is is different by leasing out your effectiveBalance? Does allowing those 100 accounts to forge with 50% of all NXT then change things?
If 100% of NXT forge, then you need 91% of all NXT for a 91% attack.
If only 20% of NXT forge, then you need only 18.2% of all NXT for a 91% attack (that number assumes that only 1.8% of all NXT forge that you dont controll)