If there are two people in the Pool on average, $6 for a 15 minute ride feels like it could be a sustainable price to me. When Pool first launched in Boston/Cambridge, I used to almost always be solo. Now, I would say that my average occupancy is 1.75 to 2 on Pool rides. It's also to the point that Pool rides seem to be cheap when they would result in Pooling and almost the same price as UberX when they'd more likely be solo.

If they're undercutting public transport and doing so at a sustainable price, I view that as healthy competition. If they're undercutting solely based on VC subsidies, that will inevitably end. In the Boston market, I think they're likely profitable on an overall basis, just as grocers are overall (very slightly) profitable, even when they sell loss-leaders and give other subsidies to consumers.