I think if you were asking this same question at the beginning of your training journey, the answer would be different. But if you're 1.5 years into a consistent xfit schedule, you're at a fitness level where PRs are hard won, not just falling into your lap anymore, and things like recovery and overtraining are very real concepts that require tweaking and experimentation.
I think if you want to lift heavier, you need to lift heavier. If you're doing 5x/wk metcons, you're maxing out what your muscles can do, and lifting heavy on the days in between is basically having no effect except to wear you out. I personally do a schedule of 3x/wk Crossfit, 2x/wk heavy lifting, but I'm only 6 months into my journey and still have fat to lose and a lot of strength to build. So I have some room to play around and my muscles are still going to make gains. Whereas you're at the point where you need to fine-tune and really dial in your training to keep making gains. It's kind of like leveling up. Congrats! You made it to Level 2!
I agree with others to cut Crossfit to no more than 2x/wk (preferably once a week), and focus on lifting.
Nope, they're doing this: The Outlaw Way It's what most of the Games-competitive Crossfit athletes I know of do (or similar programming). The WODs are free, and you need equipment, but you could find most of it at any major gym. So, you could quit your box entirely and just do Outlaw programming.The athletes making the crossfit games are "barbell" strong, "body weight" strong and "skill" strong (gymnastic movements). Am I really incorrect in thinking that it is possible to develop in all of these areas at once with the right programming? These women who can clean 200+lbs at BWs of 125 are NOT just doing SS or Wendler.
My fitness blog: Girly Pushups
I think heatseaker is right on the Outlaw training. A year ago, we qualified a team for the CF Games based on using some well established strength programs plus the MetCons. But, in the past year, all of our top athletes now seem to be using Outlaw instead. In some ways, I think it's a negative overall for our box. The top athletes rarely do the workouts with the "rest of us" any more. They have different workouts to do each day, and it has created a little bit of separation in the gym.
Even though I'm signed up for the games this year, I am happy to do my workouts based on our normal workouts, rather than trying to follow the Outlaw training. I much prefer the teamwork/camaraderie aspect of the group workout to doing separate workouts.
And to the OP, I feel pretty lucky that of the three boxes in our area, the one where I train is not only the cheapest, and the best equipped, but also has the best coach in terms of long term programming.