Any thoughts on an in-line (or other means) for measuring working loads on line?

There are several on my boat and my father's that I feel are (gasp - as a big fan of fat ropes) probably overkill for their application.

One of the cool features I see is that my halyards are relatively small lines (not tapered), but there is additional cover spliced on right where the line needs to engage the rope clutch.

Conversely, I suspect my outhaul and downhaul lines are oversized... The spin sheets may be as well, but I can't quite figure out what kind of loads that line may be under ...

And on the C&C 36 with 110% genoa, the sheets look way too big (they swelled up so they don't quite fit in the self-tailers now)