Yeah TK, I'm sure I've lost plenty of fish because of the light leader. But I'm also sure I've had many more hook-ups because of it too. In pressured waters you have to go light to fool the better fish. Sure, go 20/30lb when you're at more remote areas (like Edith Breaker her in PS), but you still need to be prepared to lose some even on that.
My biggest fish on my usual leader was a 75cm beast, and what would've been my PB I lost on 20lb so...