I was being a little facetious.
I don't see how this protocol avoids the tradeoff between transactions per second and decentralization, and just repeating the claim isn't helping me understand. You mine on old transaction, ok, so what? How does that help us any more than mining on top of recent transactions in regards to centralization?
100 Mbps allows 12'000 TPS for 1 KiB transactions. There is no an incentive to centralize with conventional hardware. VISA
peak TPS is reported to be 56'000 TPS (
https://en.bitcoin.it/wiki/Scalability). Average is 2'000 TPS.
If I'm trying to transact in Dagcoin, it doesn't matter to me that maybe 100,000 nodes could potentially have my parent transaction, the only thing that matters to me is finding the node which does have it, and that's where my new transaction is going to go. The next transaction, which relies upon mine, is similarly going to go to that node, and so on. No one wants their transactions left out on a loose strand.
On the flipside, nodes want to get as many transactions as they possibly can because that's presumably where they'll get their revenue in Dagcoin.
So there definitely is an incentive on both sides to centralize the network.
Separately, the amount of bandwidth necessary to store a transaction at VISA is orders of magnitude less than what it costs to propagate a transaction across a network. So if we were looking at your example, and say doing 2000KB/s for an average of 2000TPS, we would need at least 7000 times that bandwidth to propagate over 7000 nodes or 218.75MB/s (1750Mb/s).
Note: I'm using "node" here in the usual sense of the word; a geographically separated mining entity.