I agree. When I practice patterns mechanically, they are noticeably more awkward, clunky, and slow than when I play the same patterns in a musical context, which tends to feel far more effortless. It feels much different mentally as well, like I’m using a different part of my brain or something. Actually, now that I think about it, it feels like the difference between driving to learn to drive (focusing on the mechanical, constantly readjusting seat/mirrors/posture, thinking about my motions, etc.) and driving to get somewhere (focusing on the goal and outcome, not the process). To change lanes, I don’t think about engaging my brachioradialis to 60% then following up with a bicep flex combined with an abductor pollicis brevis squeeze, I just think “I want to be over there” and that’s where I end up.
When I practice mechanically, I also tend to think of the guitar as a sport, and develop athletic goals rather than musical ones.
With few exceptions, I don’t really practice technique separately from music anymore. Even new patterns and techniques, whenever possible I just go straight to the part where it turns into music. Repeating patterns over backing tracks feels much easier and more satisfying than playing exactly the same thing to a metronome.
When I made the conscious decision to avoid mechanical practice in favor of musical practice, the rate at which I made technical improvements jumped appreciably and instantaneously. I can’t swear it works the same for everyone, but it’s definitely worth a try in my opinion. I was pretty shocked at the difference, to be honest.