mgx's quarterly, page-6

A rational market pays no attention to previous results and only prices in future value. So the movement of a rational market is not based on results, its based on NPV of future earnings.

So yes the market is irrational.

Shares like MGX, AGO are being smashed because forward revenues are increasingly at risk and uncertain. That the brokers see more value in shorting into the weakness rather than anteing-up should warn investors it may be too hot to touch and buy into BHP - but then you'd say BHP doesn't respond to the market swings so you can't make money trading on risk. BHP "only ever goes down"...