simple equation Horth, page-24

They can also just D) write down the intangible asset values based on their impaired earning capacities and carry on.
I reckon they'd realise significant losses on assets if they went with option B) too.

However, having said that I bought back in today after selling when I didn't like the half year, it seemed to me the risk of them not getting 'synergy' was real enough then.
But if they get their house in order from here there is loads of upside. Even if they can't I think the cash flow and underlying earnings will make this a fair investment at today's prices, with or without write downs. Though this options would be underperforming to the longer term holders expectations. But good buying today I believe.