Thanks for the steem. You are an interesting person, @sigmjin. I'm still trying to work you out. You have some insightful points of view, but also seem to attract controversy and heated debates. I try to look through the bravado and point scoring of who is right or wrong and learn more about how steem works and contribute constructively to the conversation where I can.
With regards to the current topic, I think you give a good explanation of how arbitrage works, but I don't (yet) see enough evidence that price movements only go one way. That is a strong claim that goes against my intuition of how arb works and I can not yet why that would be the case. It seems from other posts you mentioned somewhere that a month ago (from just before my time here on steem), the arbitrage was going the other way and it was also coincident with increasing steem prices. To me it seems the internal market lags the external. I think the solution is more volume and arbitrage on the internal exchange not less, to decrease the price difference users experience.