3 is complex (hence the contention). One of the useful outcomes of testing soylent will be providing decent evidence on this. There are definitely some non-trivial issues going on in that several substances cause no problems in high quantities in whole foods but show signs of toxicity in small amounts from supplements (manganese, vitamin A). I am paranoid about not absorbing nutrients or poisoning myself, so I am sticking to whole foods until I see some blood panels.

4: His claim about maltodextrin being slower than sugar to absorb is wrong and can be disproved in 30 seconds with a trip to wikipedia. This does not give me faith in his process.

Protein intake is woefully low for anyone who exercises regularly.

Fat intake is contentious. One camp holds that PUFAs are bad and the other that SFAs are bad. There is little debate that MUFAs are good for you, so olive oil is a good choice. One possible modification to my shake is using skim milk and replacing the lost fat with olive oil, but this eliminates the fat soluble vitamins present in the milk which then complicates the recipe significantly trying to add them back in. I get my MUFAs in the rest of my diet by cooking in coconut milk a lot. I'm not worried about the PUFAs in the sunflower seeds because sunflower seeds have the highest concentration of vitamin E of almost any food by weight. It is highly doubtful the PUFAs are oxidizing in such an environment.