I've been trying hard to work out just how far these prospects...

I've been trying hard to work out just how far these prospects are off shore and how at risk they are in the context of the 9 dashes...

Malampaya is 62km from Matinloc island - the nearest small islands that usually appear bottom right in maps of SC58 prospects.
http://wikimapia.org/9630245/Camago-Malampaya-gasfield

I have been cross checking that with scaling 1 degree of latitude at approx 55km. By my reckoning, Balyena is about the most remote prospect and that is probably about 80km off shore.

Where exactly the disputed waters begin is not clear. Probably at about the low tide mark just off Palawan at a guess. I am pretty sure we will never see the line on any published map of the area from Nido, Philippines, China or anyone - just too embarrasing, threatening, definitive...

What we do know is that China grabbed Mischief reef (209km off south west Palawan)when they had a chance in 1994.
http://en.wikipedia.org/wiki/Mischief_Reef

From what I can make out the new leadership in Beijing has taken a more assertive public stance over the Spratlys and so there is a bit of political face on the line if there is not a bit of sabre rattling and flag waving to back it up.

Recently they have been making a presence around the Philippino marines stationed at Ayungin shoal (210km off north west Palawan)
http://www.philstar.com/headlines/2013/05/23/945475/phl-sending-unarmed-navy-ships-ayungin-shoal

I am guessing that the exploration to date is close to Malampaya for reasons of geological risk but, whether by design or otherwise, it has been pretty smart from a political risk perspective. At 80km or less offshore it may be reasonably ok.

I would say that most of the acreage to the north west is pretty much worthless in these days of increased tension. I don't think anyone needs to carve it up in to smaller SCs except perhaps to make it a less politically embarrasing farm-in prospect.

Big structures... tantalising sea bed coring results... worth hanging on to until the politics improve, or until we find the right kind of farm-in partner