So what's the point of this now that you know it won't actually delay legit transactions?
The point is to study the effects of a mempool size of >150MB which was never reached so far.
I would be interested to see how quickly transactions are able to propagate throughout the network as the size of the mempool increases. I would make a hypothesis that transactions would take substantially longer to propitiate as the mempool increases, to what extend however I am not sure.
If it is more then an additional few seconds then a new way to execute double spend transactions could have been discovered. An attacker could flood the network with transactions, then attempt to spend the same inputs twice, each originating from diverse nodes. The victim(s) would not even realize the double spend attack for a long time.
As of ~1357 GMT, around 1,400 unconfirmed transactions, total fees of ~.39 BTC and the last block was found ~4 minutes ago and 6 blocks were found in the last ~55 minutes.