I don't think any discussion of Bitcoin development should be based on assumptions that it's important to listen to those with 56.6kbps modems. Bitcoin should not be designed around the lowest common denominator of technology, just to dictate that "everyone can run it."
It should be usable by most people, but there's no reason to get hung up about fringe use cases like 56.6 modems.
That's not what havock is arguing for although he uses that argument for his argument. He wants bitcoin exactly the way it is no ifs and or buts about it.