Whilst unproved resources are risky - the often touted 10% is a...

Whilst unproved resources are risky - the often touted 10% is a little harsh.

10% was more relevant before 3d seismic
Visit APPEA and get the stats on exploration wells and seismic.
You will see that the amount of exploration wells has dropped considerably since 3d was introduced to Australia in 1994.
http://www.appea.com.au/images/stories/Statistics/Industry_Trends_Charts.xls

So - whilst explorations wells have dropped discovery rate has increased - pointing to better results.

Another relevant stat is WPL's success rate on the NW Shelf

While drilling in that hostile environment is not cheap, Woodside has an excellent track record in finding gas. Since 2003 they have had a drilling success rate of 33-50 per cent.
from:http://www.businessspectator.com.au/bs.nsf/Article/Woodside-LNG-natural-gas-PetroChina-pd20100105-ZEATS?opendocument&src=rss