Of course if he wants to do those sorts of math on a statement, maybe he needs to apply a fuller analysis to his own figures. For example the 1 trillion barrels of oil shale the vast majority is hard enough to extract that it is expected that at least 50% of the oil will be used to get it out of the rock and into something we can use, so there goes 400+ billion barrels right there. Let us note also that even the most liberal official estimates of the amount of oil shale in the US have lower bounds of 500b and upper bounds of 1.1t, so if we were to take the average rather than a number very near the top of the estimate we could take another 200b barrels out of the reserves.

Now they still aren't particularly comparable, but then neither is the actual requirements - getting hundreds of billions of barrels of oil out of the ground, refining them and transporting them to where they are needed is slightly more work than getting everyone to check their tire pressure from time to time.

Not to mention the very principle of the article seems to be dodgy: there is quite a bit of this stuff left, so we can still be lazy and waste lots of it for no reason.

official estimates of the amount of oil shale

insert recoverable into the above sentence fragment where appropriate to avoid later complaints that I am not totally accurate either. Clearly there is a fair chunk of oil shale that isn't worth extracting with any known or planned method. Who knows maybe someone will find a way, but that would be exceptionally speculative to include it in such a calculation.