It works smoothly for a smallish diagram like this, but that's as far as it goes. I attempted to create a 100% SVG music score editor and only realized my mistake after having put way too much work into it: working with large scores was sluggish to the point of making the whole thing useless. If you want snappy, I believe the best approach currently is to use a library that emulates the canvas API on WebGL (for example Pixi.js).