One example, on Hang Seng futures... currently the Aug future is about 27090 with the spot at 27160... so -70 for the EFP, while earlier it was about -50... Can you trade on that? Perhaps, but you can't really hedge it that quickly, not me and you.... so why bother? 20 points is almost 0.10%... that's a pretty decent gap... in ES that would be more than 2 points... there are some people on here that know for sure they make 2 points every day with $500 margin in ES... apparently that's 20% /day and 5000% /year (not compounded)... It's now -80 in HSI... so what do you do? meh....