Smooth, you've made a good point about spam however how do we weigh up the trade offs between limiting money velocity and spam?
I think you may have slightly misunderstood my point. It isn't that spam itself needs to be limited, it is that the system is vulnerable to a sort of denial of service from having too much data (whether that happens to be spam or "real" data, although obviously spam is less desirable) stuffed into it. Satoshi made a judgement at one time that 1 MB was an appropriate limit based on that vulnerability, considering the state of the technology, storage, propagation, etc.. What is the evidence for that vulnerability being sufficiently smaller now or in the near future that a 8x or 20x or 1000x is appropriate instead?
I'm sorry but I just see a lot of wishful thinking going on. Of course, we all want it to scale, but instead of actually improving how it scales, the proposal today is to simply push back the safety limit and change not much else. (A bit like ripping out the airbags and safety belts from a car to cut weight and make it go faster.)
I like the car analogies they've worked well for me. So "spam " just being a term for denial of service or an overload of inappropriately priced transaction data, leaves me thinking it isn't quite wishful thinking making room for it.
Reflecting on the issue has lead real smart people to find solution that I think are nonsense (picking on Sidechains here) in my experience sometimes jumping in the deep end and being overwhelmed leaving one focused on solving the issue as they happen necessity is the mother of invention and I think allowing it is a great way to do RnD, something I feel is partly in keeping with the spirit of Bitcoin.