Research (Dr Layne Norton) found that consuming protein every 4 - 6 hour produces greater Muscle Protein Synthesis rather than every three hours.
The muscles are like a sponge. A dry sponge soaks more water than a soaking wet sponge. Metaphorically speaking, muscle do the same.
Going Into Starvation
Frequent meals shut down the fat burning process via increasing insulin. Insulin blocks the fat burning process. Source: Dr John Berardi, ISSN (International Society of Sports Nutrition)
Infrequent meals, not consuming anything for longer periods, utilized fats to a great extent, especially with low to moderate activity.
As you noted, research shows that it take up to 72 hours of fasting before the body begins to catabolize nuscle.
20% Caloric Deficit
Researcher’s Drs Layne Norton and John Ivy independent came to the same conclusion on the most effective method of maintaining muscle while maximizing fat loss.
Decreasing your caloric intake approximately 20% was found to minimize muscle loss while increasing fat loss.
Another study, demonstrated a diet that rotated Decreasing Calories for two week followed by increasing calories for two week, then repeating it, optimized fat loss while maintaining muscle mass.
That due to the General Adaptation Syndrome; it take the body around two week to adapt to an increase or decrease in calories.
Once adaptation occurs, progress stops. Thus, you need to keep playing games and tricks on your body to get it to go where you want it to.
1,000 kcal Deficit
That will work for decreasing your weight. However, decreasing your caloric intake 1,000 kcal a day means you are going to lose more of your hard earn muscle mass.
If you were consuming 5,000 kcal per day, a 1,000 kcal deficit would fall into the 20% range and most like be fine
What most individual fail to realize is that Compound Exercise provide virtually the same effect as Isolation Exercises such as Triceps Pushdown, Curls, etc.
That because the “Weak Link” in a Compound Exercise is the smaller/weaker Triceps and Biceps. Thus, the Triceps and Biceps are overloaded during a Compound Exercise more so than the larger muscles.
The Squat is a great example. The weak link in the Squat is the lower back. The lower back gives out long before the legs are completely overloaded, completely worked.
That means for the legs to be completely overloaded exercises that take the lower back out of the exercise equation are necessary such as; The Leg Press, Belt Squats, Step Ups, Lunges, etc.