It's not about the energy content of the oil. The interest in algae farming is all about producing the greatest amount of oil, WITHOUT using productive, fertile agricultural land that could be producing food crops.
The guy is pretty much on target with the scale of oil production (theoretical) when talking about an algae farm versus a typical row crop (corn, soy, etc.). I think his statements of selecting algea strains for differing fuel types is a little ambitious. The foremost issue with algea based fuels right now is the cultivation of high oil (lipid) strains, and more importantly, the extraction of this oil.
Once the oil is extracted, there are proven means of turning the oil into biodiesel fuel.
http://www.bayarearidersforum.com/forums/showpost.php?p=3867200&postcount=104
You can park these algea farms in the middle of the desert as they have plenty of sun and non-arable land, or park them next to a coal fired facilty and use them as exhaust stream scrubber.