Hey, Gina! Yeah, I didn't find those original calculations difficult either. For some, though, they seem to be mind-boggling.
I don't think it's critical to find the EXACT amount, since they are after all MINIMUM requirements. I mean, a 27-gram serving of meat is about 4 ounces; a 40-gram serving is about 6 ounces. ANYONE can eat 6 ounces of protein per meal. It doesn't all have to be "meat," either. Add some cheese (even Philly cheese), maybe some heavy cream. Easy.
The first time I tried PP, I literally paid no attention to ANYTHING except the carbs and protein. I tried for 34 grams per meal (about 5 ounces), and no more than 7 carbs per meal. At first, I did 3 meals at 2 carbs each, and 2 snacks of a couple carbs each. My fat intake didn't even come into my thinking at all.
Also, you said:
So I don't recalculate as frequently as the weight changes and the protein requirement changes
Really, you don't need to worry about this AT ALL. Remember, these are MINIMUM requirements. The difference between a 40-gram serving of protein (remember, that's 6 ounces of meat) and a 27-gram serving of protein (that's 4 ounces of meat) is only 2 ounces
. Even if you never reduced your intake of protein, you'd still be good to go. Just keep those carbs in check.
BEWARE CARB CREEP! That's what I'm experiencing now. Sure, 5 Ritz crackers are only about 10 carbs. That means I can have 15 and be fine for the day. But then there are the other little carbs that I have throughout the day. That, and grains tend to send me off on a binge. OK, not a "binge" per se, but grains tend to set off cravings.
It's all about getting back to the basics. Conquer the basics, and you've got it made!