GT, I like how you think. Agreed. That would be the probable way fundamentally unwarranted arbitrage seems to return historically. You note a jumping of ship investment macro thinking wise. Perhaps. I note historically that dwindling trading volume leads to arbitrage shrinkage and conversely when traders move in on both BKIR.L and IRE en masse the premium grows.
My only logical reasoning as to why that is and pragmatic, understandable, to me is that traders are by trade and not fundies guys and don't know any of this - and investors are investors not TA traders and they do not drive volume. One of my best friends is an ex Lower Manhattan trader who now lives in Miami and calls me all the time about fundies stuff he is clueless about. And I know next to nothing about big board TA trading and will be the first to admit it.