[EricH]

Every alternative energy drivetrain has roadblocks. True.

Why not focus on developing better engines of your favorite variety (diesel or gas)?

Because at some point, it becomes economically non-viable to do so. If it was economically viable to engineer an engine to have 60 MPG right now, you can bet that somebody would have done so! But at the present time, it's not economically viable. Give it a couple of years or so.

Why are people working on EV technology? Because it may not be economically viable right now, but it's getting very close. As soon as it is, you can bet that the companies that currently have the technology to make EVs will be making money hand over fist, as they'll either have the market-ready stuff, or they'll be making a lot in patent royalties from other companies that are building EVs using their technology. And, what they're working on can improve the hybrids.

The obstacles to an EV are simple: Range (how far you can drive without charging), Price (those batteries are expensive), Charge time, Performance, Size/weight. All of those are improving.