I've got these LaBella Jamersons that I've finally managed to setup nicely at low-medium action on my P-Bass. My plucking fingers LOVE them; they are my favorite strings thus far for finger-style play. It's not just the fact they've got a lot of meat to grab, but they've got a bouncy resistance that I enjoy. They are responsive to both a light and heavy touch, and even compared to the lighter FL and FS sets I've tried, they just sound different: authoritative, woody, and wonky (in a good way). And they unexpectedly sound better than ever through the amp I just purchased, so I'm reluctant to give up on them. But my fretting hand and arm after 2-3 days of play/practice protest in a way that feels more than just general fatigue. I've managed to get the action lower and the E intonated better than my previous three attempts, and this seems to help greatly when actually playing. But today, I experienced something akin to a Charlie-horse spasm when driving in my fretting forearm that temporarily left me unable to hold the steering wheel with my left hand. And since this happened, I've had a dull but persistent pain in the same forearm and just above my elbow. The blame seems obvious: the strings are just too heavy. Perhaps, but I suspect it is more about deficient technique. I've got long, skinny fingers and thumbs. I've still got a bad habit of overextending my thumb behind the neck to pivot rather than shifting my whole hand. Having the action lower reduces the effort in grip, but having slender fingertips feels like I have to focus a bit more when fretting to keep from rolling off the larger strings with my ring/little fingers. I don't have big, thick bear paws, and I never will, but I'm hopeful I can play anything with some adaptation. Without the benefit of examining my technical flaws, am I just too optimistic thinking my hands could somehow be compatible with these beasts? Maybe tweaking my technique is the answer, or just more time building up strength, but I don't want to needlessly persevere and do damage when smaller sets do get close. Has anyone encountered something similar and found a way to make them work?