Clemency, I would like to touch on the CrossFit connection.
Before my first Whole 30 in July of this year, I was working out like your average chick. I would go to the gym very regularly to lift weights and do cardio. Sometimes I would go twice in a day to get fasted cardio in the AM and do weights at night. I was meeting with a personal trainer once a week for 30 minutes. I did all of this to change my appearance. I was trying hard to lose something like 7 pounds. THat is a lot of effort for 7 pounds of vanity.
I was also doing some weird things with my diet to get rid of the 7 pounds including: weighing, measuring and calorie counting every bite of food in my body, drinking like a gallon of water a day (seriously unnecessary), even doing "carb cycling" and generally obsessing about my body image. I really thought I was healthy because I was active and ate "right".
Then came my Whole 30 where I began to see the harm in what I was doing day in and day out. It was almost an out of body experience, I was up in the sky looking down at myself and had an "Aha!" moment. Everything I was doing was in vain. I took a break from the gym and slowly started leaning towards CrossFit. The reason is that CF is about fitness not vanity. There are no mirrors. The gym is dirty. It's in a warehouse. Nobody gives a shit what you look like or how much you lift, just as long as you put in the effort. I saw in a CF video not long ago where someone walked into a CF gym and said "Where are all the machines?"..."We are the machines."
I went from trying to have the cutest workout clothes to wearing T-shirts again. I don't want to worry about what I look like when I am trying to move a bunch of weight in a short period of time.
Basically...the ideas behind the Whole30 and CrossFit kind of go together, but not purposefully so. They are both geared towards optimal health in an inordinate way.
I thought I would also mention that I stopped counting, measuring and worrying about how much I was eating and focused on what I was eating. The pounds and bloat melted off my body while I took a break from working out, slept more and ate real foods. I actually didn't start CrossFIt until after my Whole 30 was over because, like you, I wanted to focus on one thing at a time. There is nothing more special then being the very last person to finish a workout and have 8 other people cheer you on. No one would ever do that in a regular gym.