Of course, I come from a country where "Featherstonhaugh" is pronounced "Fanshaw" and "Cholmondeley" is "Chumley", so I'm hardly in a position to take umbrage at such heterographic extravagance, but I was still curious as to what was going on.
Someone on Facebook just supplied the answer. Another way to read the sounds in "takanashi" is as "鷹無し" where 鷹 (taka) = "hawk" and 無し (nashi) = "without." The idea is that, if there is no hawk then small birds can play safely - hence, 小鳥遊. Ingenious, huh?
Whether it's a modern innovation or not, I'm not sure (I'd like to know); but I also wonder whether there are any other examples of this type? I can't think of any equivalent in English, although some of the puns in heraldic devices may come close.