In my experience it's only moderately helpful, and often plain useless, for exactly the reason you mention. It does not handle 'mixed modes' (or whatever you want to call it) at all. I have two places of work and sometimes work from home, but i can only set one location as work. I commute sometimes by bike or walking, sometimes by train, and rarely by car (but it does happen). But; according to Google you can only have one mode of transport. There's probably a pattern to my madness but it does not seem like Google is smart enough to find out (which is hard to believe). For now this is aimed at the american suburbanite soccer mom i guess (and as a, albeit european, semi-suburban dad i'm not even that far from that demographic).