Seems to me these Frenchies are just the latest in a long line to get excited about Iran's euro bourse.
George Ure (Urban Survival), the Financial Sense Online folk, and other so-called "doom and gloomers" (I prefer to think of them as unsentimental realists) have been mentioning it for some time, as have geopolitical commentators like those at From The Wilderness Publications. Energybulletin.net is another good domain to back-search for analysis of this development.
Interestingly, William Clark's 2005 book "Petrodollar Warfare" has a chart in it which suggests that OPEC has been pricing oil in euros since 2001. Figures quoted on page 140:
2001: US Import 3.5b @ $21.40/barrel. Avg exchange USD/EUR = 0.8952. Euro price per barrel = 23.91
2002: US Import 3.4b @ $22.61/barrel. Avg exchange USD/EUR = 0.9454. Euro price per barrel = 23.92
2003: US Import 3.7b @ $26.97/barrel. Avg exchange USD/EUR = 1.1321. Euro price per barrel = 23.82
Anyone want to run the figures on 2004-2005?
Now back to this French Institute. No matter how hilarious their faux-scientific presentation, they should probably have speculated as to the anticipated volume of this oil market. They say it will be available to all oil producers in the region. Can't see the House of Saud openly abandoning the U.S. dollar somehow, and an occupied Iraq clearly will not return to the late-Saddam-era policy of pricing their oil in Euros. Syria will come to the party but they produce a paltry 500,000 bpd. So, with Iran's 4m bpd, that's a little over 5% of world production, currently worth about $250 billion USD/year (roughly 210b euro).
In my opinion this won't immediately do much to destabilize plans for a CONTROLLED demolition of the USD. It'll take time for this market to gain regional support, if it ever does, to bring it up to a level where it is a serious competitor to the London and NY markets. US threats, intimidation, and carefully orchestrated "mistakes" should be enough to delay things. An invasion is unnecessary -- securing the Khuzestan oilfields in the southwest may even be logistically beyond the capability of the US military + ally.
On the other hand, perhaps a few dozen well placed EMPs may be all it would take to reduce Iran to the desired state of economic serfdom and send an appropriate message to the rebel scum in Europe and beyond.
"Fire up those printing presses, we're going shopping!"