I personally disagree with some of Martial Artist's claims, like there is this sense of a "higher self" that goes beyond
our own thoughts (where else would they come from?). However, the topic is not about his views. For a formal critique of his guide:
I definitely agree with him about the comfortable posture suggestion. To not move for long periods of time either 1) requires the will to resist against ones urges to move or 2) have no urge to move in the first place. Obviously he is aiming for the 2nd reason, which is the easier way to go if you are not an expert. Setting the time watch also gives oneself the heads-up, and a sense of an organized practice, that the practice is legit, in the sense there is a possibility of completing it (stretch). Or the time limit can just make sure the person doesn't fall asleep; either one, ha ha ha. The only part I dislike is how he overly-generalizes the last step of his method. I think the following saying is perfect for this type of situation: "Easier said than done" (Don't know who was the first guy to say it). I must admit, teaching others how to succeed in the last step is also
incredibly difficult, if you are the type of person who likes to move. It's hard to expect from anybody to clearly explain to everybody else how to follow through with the last step; can't help but at least admit the guy tried to give some honest effort.
Off-topic: Not only do I disagree with his views, but I also think he needs to add some more meat

For something abstract like the "mind", "desire", and "peace", they have to be clearly defined if they ever hope the reader can completely understand the hell they are saying. For example, it's possible to be physically at peace, but being at peace with "oneself" (mentally-speaking, as in our ego with our self-criticism) is completely different. Honestly, this practice is aimed to develop
discipline over ones mind. Sure, you can develop control, but does that mean you completely understand yourself inside and out? Possibly. But it's not guaranteed. I also chuckled when he said the method is a "short-cut" to self-mastery; there are no such things as "short-cuts" when it comes to oneself, since from what experience can you compare the effort against? It's too abstract to quantify/measure (not to mention 110% biased). Mastery is not only being "the best" in a subject in terms of speed, but it's also an individual's understanding in that particular area. To connect this with psionics; you can't be considered as a master, at least by your own standing, unless 1) you have extremely fine control over/sensing of psi ("fine" being relative to what? I guess relative to how everybody else is doing, but it's more like how comfortable, and how much of an impact you can make towards your surroundings, that plays the main factors) and 2) if you have at least contributed to the field of psionics' research/ideology (no offense, but there's (
biased) hardly any concrete evidence to work with supporting the notion of possibility that psi exists (shown through lack of studies)). Reason 2 indirectly shows how well you understand psionics as a whole, while exploring inside and out how, and why is, psionics important in terms of humans' perspective (this last one is not important as the first part of reason 2. Honestly, if you understand the theory/reasons behind psionics, then expanding the field with your own theories/observations isn't that difficult.
Usually ones understanding in such a subjective field can be gauged by comparing your ideas with others' ideas. Scratch that last one; understanding is more from an individual effort. To be accepted as a master
by others requires clear reasoning, a common ground on what are the axioms allowed between you and the others, and some form of agreement (in terms if it's possible for a certain concept to be up for interpretation) if your ideas are possible within the confined (and agreed) set of axioms). In other words, you have to understand the significance of this meditation practice, how it allows self-mastery (if it indeed does), and how this method can/cannot be refined further than it is already to start you off. These are not some easy questions to answer, so it goes to show how difficult the path to self-mastery can actually be.