"I'm not sure I understand all the pluses (+) and minuses (-) we've seen in the titles of the workouts lately. What are they and why do you do it?"

They are indications that something has changed about an established workout. 

I like apples to apples comparisons. Comparing your numbers (time to completion, weights used, rounds completed, etc.) from one workout to another is a fantastic way to gauge your health and fitness progress.

Problem is, if I changed something about a workout and you are trying to compare your progress within that workout with one we've done earlier, it might give you a false sense of achievement and/or failure. 

I try to NEVER change workouts. Once I have it crafted, tested and put onto you, I like to leave it alone. But, this isn't always practical. Take yesterday for example. We dropped the burpees from the "Abs-Mash" workout. Judy had it mostly right in comments when she wrote, "He was trying to avoid the revolt that would have followed from burpees two days in a row...." 

That many burpees 2 days in a row, generally, isn't smart. So we dropped them for that specific workout JUST THIS TIME. Although we've been known to do it before. Probably will do it again?

The Abs-Mash workout fit perfectly with our programming for the week. So, SOMETIMES, it's just better to make slight changes to a proven workout to serve our programming purposes. Like I said, I HATE to do this. It screws things up sometimes. It would screw them up worse if I didn't indicate the changes somehow. The best way I've learned to do this is to let you know if I am adding work, or subtracting work from the workout.

A minus (-) means I took something out of the workout without replacing it.

A plus (+) means I added more to it. 

If I change a movement inside a workout to fit our programming for the week, I'll also let you know. I'll indicate this by telling you what I sub'd out ("sub'd run" means I took OUT the run for rope jumps), or I'll let you know what I'm subbing in ("sub curls" means I put curls in there instead of, say press jacks). 

These indications ("-," "+," "sub'd," "sub") makes it easier for you to search your results for this workout (please tell me you do this!?) from last time we did it, or one exactly like it. Therefore making it easier for you to gauge your progress.