Well, if you're not spending time **Practicing** orchestra parts and Actually Performing orchestra parts IN AN ORCHESTRA, guess what? You're not learning how to play in an orchestra!
You might not realize the differences when you do get to play in an orchestra, but everyone around you *will* notice.... Playing orchestra parts is not about projecting your tone, vibrato and musical idea to the back of the hall, but it's about you *joining* everyone else on stage in making the *same* tone, rhythm, tempo, bowing and musical intent, (and often *not* slow bow, and *not* anywhere close to the bridge - which took me along time to believe and understand after reveling in the glorious sound that Gary help me get).
Gary Karr's gorgeous style and "Orchestra" style really are very different approaches to music making on the bass - and "Orchestra" style just-so-happens to be the approach that classical bass players need to master if they want a paycheck for playing music - even if they're so lucky as to land a university teaching position, their students will also need orchestral "wisdom" in addition to solo skills.
You're lucky to have the "Gary" style under your belt, but consider it as *part* of your Portfolio that you can Use As Needed in orchestra or chamber music; Big, Bold and Beautiful sound is great solo, but when you're One Voice in the "choir" that is The Orchestra, you gotta have a big portfolio of sounds and styles, ... so perhaps the next school or teacher you work with, it's okay to look for someone who has, and teaches, Orchestral experience!