Your paper is fundamentally flawed because it addresses nothing resembling the current dynamics at stake in Bitcoin. More precisely it ignores the incentives for miners to centralize (as they have shown to have) to mitigate propagation times. In effect your paper clearly demonstrates it is more profitable to do so under free-floating blocks and you essentially rely on their altruism to maintain the validity of your model to make decisions going forward. In short, your work might be sound from a technical standpoint but can not be used to construct security models that depend on worst-behaviours assumptions.