Yes, "ko ryu" can be written in a way that means "tiger (and) dragon", but I believe you realise that that is not what pgsmith was refering to. And, no, no matter how much reference material you have, no matter how much self-training you have, no matter how much personal insight you have, if you want the old arts you have to train the old arts. Legitimately.
I have many reference books on many old systems, but would not consider myself a practitioner of those arts (even when my reference books include all the technical work of a particular art, because the technical side is just a beginning). As stated, "Musashi's style" (Hyoho Niten Ichi Ryu) is much more than just two sword techniques. In fact, the two sword kata set is the shortest of each of the three sets of kenjutsu kata within the school. For the record, they include a 12 kata set for the long sword, a 7 kata set for the short sword against long sword, and a 5 kata set for two swords against a long sword.
But the essence of Musashi's approach to swordsmanship (evident is you read the Go Rin No Sho) is not the use of two swords at once, instead it is on the ability to wield any item well and independant of itself. Two swords is merely one application of the work. In fact, the book deals with long swords, short swords, two swords, swords from other arts, spears, naginata, and other weapons, with the only technical points (techniques) focusing on long sword against long sword (the Water Book). As stated, I have never heard of anyone using two long swords together, however your idea would be a good one for conditioning the wrists and forearms, just not greatly practical.
Oh, and back on Tiger and Dragon, if we're going to use that reference, we might as well use it with some context. The use of Tiger and Dragon is an implication of completeness in many ways, with the Tiger being Lord of the ground, aggressive, focused on striking and leaping forward, and the Dragon being the Lord of the air, focusing on grabbing (often depicted holding ball or pearl), present in the moment at all times. So to say that "koryu" can mean "Tiger and Dragon", to me, says that to understand Koryu you need to experience the inside and outside (all aspects) of the art in question, and you just don't get that from books, videos, dvds, or even forums. You get it from learning the Koryu art from a recognised teacher.