MAF is specific to you (Maximum Aerobic Function) it is the heart rate in which you are the most metabolically efficient. Your body utilizes fat the most efficiently at your MAF heart rate.

MAT represents the type of training you are performing. (Maximum Aerobic Threshold). It is a work to rest ratio program that works to develop your aerobic system for different time domains. Ticker uses MAT training to increase your MAF. 

You should spend as much time around your MAF as possible to improve it. You may have to scale weight and reps because when you are not metabolically efficient your heart reacts dramatically to small increases in intensity. As you progress this becomes less dramatic and the spikes do not occur as easily.
No. But when you are trying to repair your metabolic system, a really strenuous lifting session can slow your progress towards improving your MAF. This is why Ticker recommends everyone to stay at lower percentages of max lifts when in metabolic repair. Spending time in lower percentages is a great time to fix bad habits and to become efficient while enjoying the lighter weights.
All MAT work should be as close to your MAF as possible. When you are damaged metabolically spending more time at your MAF is how you can have the greatest impact on improving your MAF. Do GOAT and class at your MAF, yes!
Absolutely! As much as 70% of your metabolic changes can be tied to your eating habits. To fix your system, you must reduce stress and inflammation. If you are eating junk food, your progress will be slower. Junk food is anything with a wrapper; even the marketed “healthy” bars, quick snacks for athletes, and cheap whey protein. Add healthy fats, whole real foods, and clean protein to your diet. When you do consume complex carbohydrates, balance them with fat to teach your body to use them effectively.
Any program that is an extreme option, relating to diet, fitness, or even lifestyle, is typically not sustainable forever. Learning what unique balance of foods your body needs to perform at your current level of training and where you are in life, is the best way to structure your nutrition. Fat adapted athletes do need a high fat diet but their requirements are also balanced by the other whole foods they eat.
Burning fat as a fuel source during exercise is the least stressful metabolically speaking. Your body burns fat efficiently over long periods of time without adding undue inflammation; this is how you can function doing active household chores for example, without being sore and over-tired, why not feel the same way during and after exercise and then have the lean body composition to match for long-term health?

Yeah it’s unfair but some people have genetics on their side, or they have spent significant time developing their aerobic system.

Your MAF is specific to you. If your MAF is really low and you can’t do much work at it, that just means you are metabolically inefficient, and you have to be patient, relax and enjoy the “easy” training.  If your MAF is low but you can do a lot of work at it that just means you either have a lower genetic HR or you are going to see fast improvements by training at your MAF.
Yes. Ticker athletes are seeing dramatic changes while training at their MAF. The more you train at your MAF, the more it will increase. You can lower it by training at too high intensity and/or training too often, by eating junk food, or by not sleeping well. Reduce your stress, increase your MAF.
Intensity can be good! It’s just should not be abused. High intensity used appropriately will improve your aerobic system. Used to often, it creates stress and an inability to recover. Intensity should only be added if you are at your optimal MAF heart rate,10% or less of your training should be done at high intensity.

MAT 10 is a training interval of an hour or more.

MAT 1 is :30 with 1 minute of rest.

MAT 5 is 3 min of work with 1-2 minutes of rest.

In general terms, the goal for everyone should be to have a MAF HR that is 180 – age. This is a sign of metabolic efficiency. That person can usually train Ticker without stopping, scaling etc. assuming skill and muscle endurance is not an issue. This is of course a general statement and everyone is different. The best way to know for sure is to have a metabolic efficiency test performed.