Sparring is a whole different thing from working technique. And it's a symbiotic relationship in that it gives you a context for the skill-work you do.
I jumped into sparring as quickly as a could for a couple reasons:
1) Fighting is what MT is about. It's not some abstracted TMA where you focus on forms, or pretend you can kill someone with a single mighty blow (too powerful to practice on eachother). If I was going to do MT, I really wanted to do it. Some people HATE being hit. That's just the way it is. Some people can't deal with it and don't enjoy that. And even the context matters (some peopel don't mind having their arm cranked to the moon, but don't hit them in the face). So I wanted to get in their and see if 'real' trainign was something I could even deal with before investing time and money in something I'd never want to do "for realz".
2) Is the context thing: you just improve so much faster when you're actually learning for yourself what works and what doesn't. It allows you to frame bag/mitt techniques in terms of sparring/fighting, and not just abstractly or against a bag/mitt.
I agree to what you say. I am just a average guy. But what you say totally true.