It's rather involved and confusing, and during the time of trying to nail eating more and right macros, it can make it harder.
It's focus is for lifting, and feeding the chance to build muscle when you can, but take deficit on other day. So less days at deficit means slower weight loss.

The idea for eating more on the day of lifting falls apart if you work out in the evening. Because the repair is happening out 24-48 hrs, and you can easily be more hungry the day after, and that's when you need the increased food.

The same theory can be made to happen when eating the same amount daily. You just shove the majority of the day's calories in to the 24 hrs post lifting workout. Same effect, giving the body more calories during the time it would be willing to build muscle, less calories during another 24 hr period.

A form of what that site is doing is on the TDEE Deficit tab, in the bottom deficit section, for calorie cycling.
It's based on amount of BF%, and total lifting focus with no cardio above walking.

You'd fill out Simple Setup tab Activity Calc as normal for mainly the lifting and no heavy cardio (you'll actually be informed of this option right then).
Then go to TDEE Deficit tab, that Deficit section, enter the TDEE that is shown on the Simple Setup tab.
Go to the Calorie Cycling method, and it will show you your 2 different day's TDEG.
And the amount to log the workout as to get the level right.
And how often and how much a refeed should be done.
Should still try to balance each day's eating so more calories is consumed during the 24 hrs post lifting workout.

This is the whole method that LeanGains uses, combined with much more strict macro usage and different level.

Thanks so much for the reply, heybales. I really appreciate it.

Okay, so I should probably just stick with the same amount of calories every day then because I work out in the evenings after work. Is that correct?

I recently cut back on cardio, but have been doing a Body Pump class 3 times a week, using weights heavy enough that I can *barely* make it through each set of exercises without a break. My arms (and legs) are usually like jello by the time the 60 minute class is over. (I don't use a barbell due to elbow issues, so I use free weights for the class.) I think it must be working because I just had to up my weights for back, chest, and shoulders. I had been doing Insanity at least 3-4 days a week until about a month ago, but now am doing it only 1 day a week, weight lifting class 3 days a week, lower intensity cardio 1 day a week, and two non-consecutive rest days.

So do you think I should go by the number on the spreadsheet where it says "Deficit is 0.7% of current weight, to potentially allow gaining LBM during deficit" because of the weight lifting class 3 days a week?

No, too much other cardio. Same amount daily, still do the daily shove of calories I described above if desired to improve things.

The Simple Setup tab still uses that method though, and balances it with how much high cardio you have entered in the Activity Calc.
If none, you get the same value anyway. If you have cardio time there, it's a sliding scale towards more appropriate 10-20% off depending on amount to lose.

So don't worry, you are getting a deeper deficit if doing lifting, compared to doing just cardio.

Okay, so one last question then. You had helped me in another thread with adjusting my height on my BMF armband to reflect my actual BMR. I do feel like I'm getting more accurate numbers with it now. When looking at calories burned during sleep, it now reflects the same BMR I calculated in the BMR calculator at gymtools.com (based on tested RMR).

I always considered myself lightly to moderately active, but the BMF armband consistently now gives me 4-5 hours a day of moderate to vigorous physical activity, which includes my workouts and any other moving around I do during the day. On the armband software, I have the "moderate" setting at 3-6 METS and the "vigorous" setting at above 6 METS. Should I go by the armband numbers when entering numbers in on the Activity Calculator on the Simple Setup tab?

Well, the medium cardio level for walking 3 to 4 mph is equal to 3.3 to 4.9 MET's.

So the scales measures are not the same. 3 MET's is about 2.6 mph level walking, which is middle of light cardio level. 6 MET's is walking level 4.45 mph, barely into the high cardio level.

If really curious to match them up, you could adjust the BMF settings for Moderate to be 3.3 to 4.9 MET's, Then Vigorous is 4.9 and above.

But if you are syncing with the BMF, the use of the spreadsheet may or may not be useful.
Best bet is average 5 typical non-exercise days together for avg non-exercise TDEE.

Then in Activity Calc remove everything, and increase the service trades or labor trades until the shown TDEE match what BMF is reporting.
Now you have non-exercise TDEE matched.
Now add your exercise time and type in the calc, not what BMF is reporting for levels, because some exercise it can't be as accurate with.
Now, the new TDEE calculated may end up being close to the BMF avg weekly TDEE, if the exercise is the type it can decently estimate calorie burns on.