If there was a way to progressively enhance based on available resources (connection speed, usage metering, device performance, battery charge) we wouldn't have

If there was a way to progressively enhance based on available resources (connection speed, usage metering, device performance, battery charge) we wouldn't have to compromise. As it is, you either design something really bare for the worst connection (which works for some content, but not all, and keeps us from effectively using the power we have in our devices) and serve it for all devices/connections, or design something for a mid-tier device/connection, which amounts to a bad experience on weak devices/connections and an unimaginative experience on better devices.