I may be wrong, but my impression is that the need for long leaders is primarily to minimize drag, particularly for dry fly fishing on spring creeks where there are a lot more small current variations in the glassy smooth surface than you can imagine. For wet fly fishing, which is what I was doing, I really do not think a long leader is critical. I've frequently read of streamer fishermen only using 3-4' of surprisingly thick tippet.

When the line is a supple as John's furled tenkara line, or as thin and supple as the line I was using that day (equivalent to 2x tippet diameter), combined with the ability to minimize drag that tenkara fishing provides, it really doesn't seem to matter that the clear tippet is pretty short.

I've found some hi-vis fluoro that should be thin enough to actually use for the tippet. I'll try it to carry the colored line question to it's logical conclusion.