Definitely feasible, I didn't know any Japanese. There is English almost everywhere and many people are happy to be practicing their English with you. Though I

Definitely feasible, I didn't know any Japanese. There is English almost everywhere and many people are happy to be practicing their English with you. Though I ended up learning some phrases while there so I could be more polite. The restaurant protocol really helped, and "sorry", "excuse me", "thank you", "hello", "goodbye" were all helpful. The trouble with using only some Japanese is you will get a reply in Japanese and not understand it, so sometimes it's best just to be up front that you don't know it. The trains themselves are effortless once you do your first one. You quickly learn the floor markings on the platform, and you can't mess it up too badly because if you miss one, the next one isn't far behind.