While it's great to know everything, I don't think it's feasible to learn all of orthobullets as an M3. I'm an intern and still haven't gone through it all. To do well on rotations, study for your cases by figuring out the schedule for the surgeon or service you're on, then gearing your study to those topics. Focus heavily on the surgical approach/anatomy for that approach with Hoppenfeld's/Netter's. You can try to read through the notes to determine what the surgical plan is for the patients (Epic makes this easy, not sure about other EMRs). If you don't have access to the schedule or notes online, go to the OR front desk to get the schedule ahead of time and realize there could be add-ons after you get the schedule. This is more difficult when on trauma for obvious reasons. For clinic, if you have EMR access you can almost "cheat" by looking up the patients the night before and: 1) if they're following up, you know what has already happened and what the plan is going forward, or 2) you can see there's a new patient scheduled with X complaint and possibly has imaging completed that you might be able to view. Also, you see how they write their notes and what things they focus on for the history and physical exam (make sure to learn how to do the exam maneuvers you see in the notes so you can perform them and report them appropriately). I say cheat because you can make it look like you know all of orthobullets, when in reality you just focused your study to what you're currently seeing. It's just preparing appropriately and staying focused - ortho is a huge field.
Also, Handbook of Fractures is great for trauma and I would read the section for whatever injury you're seeing. AO Surgery Reference is a great free app for some principals.
To answer your actual question, I used orthobullets to quickly read about topics I was seeing in clinic or the OR. Sometimes I literally only had time to read a few lines while turning over rooms so I had some idea of what we were doing. As a resident I feel like I'm going through it more systematically. Generally, you're going to be asked anatomy stuff as an M3/M4.
Hope this helps!