@cypherdoc:
Neither do I believe that selfish mining is a serious threat. The point I'm trying to make is that given Eyal and Sirer's assumptions, the paper is mathematically correct. You can argue that their assumptions are not realistic (what you appear to be doing), or you can show that they made an error in their analysis (I don't believe they have). Craig Wright did neither.
This is what I originally thought until I read the paper in more detail. They do NOT actually assume that the race has 50:50 odds. They solve the problem for all odds between 0:100 and 100:0. This is the γ coefficient in their paper. With γ=1 (the selfish miner wins all races), the selfish mining attack is profitable regardless of the miner's hash power. With γ=0 (the selfish miner loses all races), the selfish mining attack
is still profitable but only if the miner's hash power is greater than 33.3% of the network total. This is summarized in Eyal and Sirer's Fig. 2:
Yes, I completely agree. The attack only becomes profitable after the difficulty re-adjusts and long after the world has realized that the attack is taking place. I don't think miners would take this risk.
My take on Sirer is that when he first got into Bitcoin, he wasn't taking it that seriously. He came across to us as a total dick after publishing his selfish mining paper (he tweeted that Bitcoin was fatally flawed and that everyone should sell their coins...IMO bad behaviour for a CS professor). Since then, I think he's realized both that Bitcoin is a goldmine for future research and that our community is full of serious researchers and developers who he now respects. I think you two might actually get along if you had met under different circumstances.
I agree again. The Eyal and Sirer model is very simple and doesn't take into account the complexity of human behaviour. But as an academic paper, their work is still correct (given their assumptions) and valueable (given the research and thought they've inspired).