Here's the story ...
Baby Bats were small cheap plastic single-line delta kites, sold in the US in the 1970s. So, basically, they were contemporary to Peter Powells in Europe. In an article in the Spring 1979 issue of the Kite Lines magazine, Red Braswell (then president of the AKA) describes a method by which Richard Radcliffe rebridled these little kites for dual-line flying, called 'figurekiting' in those days, and a re-bridled Baby Bat won 1st place for two-line kites at the Maryland Kite Festival on April 29, 1978. Clearly, a dual-line kite like that caused a bit of sensation! The Kite Lines issue, where you can read the entire article (on page 46), is here, but the crucial bit is the 'Radcliffe Bridle':
Getting me grubby hands on the kites took some time, but I was finally successful in getting my hands on a Gayla Baby Bat and a Gayla Sky Spy, both brand new, for $10 each! Shipping from the US cost more than the kites themselves, but, hey,who cares?
First flew both as single-liners, and they flew exactly as I expected: like cheap little plastic delta kites.
That didn't inspire much confidence that they'd fly halfway decent with two lines, obviously .... Still, I had to try it out! Adding the bridles, and strengthening the leading edges in the process, took maybe an hour and a half, and the moment of truth arrived the next time we were on the flying field ...
To my great surprise, they flew pretty well on two lines!! Much more steerable than I expected, although of course not in the same league as a modern dual-line kite. And they do need a decent wind to keep going: if the wind drops away, they become very difficult to turn.
But we managed to let the kites follow each other in infinities, ladders up and down, wraps, and even some boxes. It actually worked so well, that we're even considering flying them to music as a 'quirky' routine one day. And this classic fits the character of the kites really well: