In other words would you be interested, if offered by a mobile phone co to pay double the amount you'd pay per month for a 24 month contract but for only 12 months?

Interesting question, but no.

I'll get the benefits for twice as long, for essentially the same price.

I also get to keep more of my money in the bank over time, allowing me to gain interest on it rather than someone else (no matter how small that interest will be).

No why would you be?

People on iPhone contracts already do don't they.....pay more for less I mean?

The world is full of idiots who do this all the time!!!!!!! Would I? definitely not. Then again I would never take out a phone contract...

I would pay slightly more for a shorter contract as i like more frequent upgrades. I certainly wouldn't pay anywhere near double though.

Your exact example is crazy. You are getting the same physical phone, half the service and the phone company is getting their debt from you paid back twice as quick.