The additionality test is burdensome to a capitalist out to turn a quick buck on a ghg reduction, so red herrings are expected. This red herring goes with simple-minded approaches seeking profit from more efficient coalgeneration, an approach likewise showing no conscience for leaving local environments in the lurch, as the Casten's subscribe to (another article below harping on burdensome regulations for clean air).

Between the extra transaction cost and the uncertainty endemic in offsets, the immediate solution to any additionality quandary is to agree polluters in covered sectors not be allowed to use offsets to get out from under a cap, as found in Lie-War. Offsets should be strictly voluntary for those wishing to act responsibly in an additional way, not a black hole for a covered polluter to hide.

Waste Not  A steamy greenwash to global warming
http://www.theatlantic.com/doc/200805/recycled-steam

The whole purpose of high-quality, additional offsets is to encourage carbon reductions in sectors of the economy not otherwise covered by a cap. The purpose of allowances is to force carbon reductions in the sectors that are covered. Getting rid of additionality would damage both mechanisms simultaneously.

In other words, don't force additionality tests on all carbon reduction mechanisms. Keep them on the carbon offset market but not the cap and trade market. The carbon offset market (your business) holds potential to reduce GHG in addition to that achieved under a cap and trade market and it needs additionality tests to keep everyone honest. We need to keep the two ideas separate. The requirement to prove additionality  would strangle cap and trade with red tape.

In the end, it all comes down to biodiversity. Poison Darts--Protecting the biodiversity of our world