Agreed, one is for a play while the other is for a single...

Agreed, one is for a play while the other is for a single well.

50-50 for Icewine relates to the overall shale play, not any one well.  Remember, it was 25% for the overall play before IW1 (which was 100% successful in achieving all it sought to achieve), then went to 50% pre-IW2, and remains unchanged at 50% despite the less than ideal outcome (so far) with IW2.

While for the conventional well, the 25-30% relates to chance of this drill getting to target zone and finding commercial quantities of extractable oil.  Another way of looking at it is the Nanushuk conventional play has 100% CoS in certain acreage, but that does not mean that every well seeking to penetrate it will be successful - even in proven acreage.  Moreso (or rather, less so) in our case as our acreage is yet to establish it contains productive reservoirs of this play.