So if you have any battery problems they essentially have to replace the entire machine?
This is the problem. If you want a computer to last 3+ years, you WILL experience a dying battery.
This is it, folks! We're at the point where laptops are too thin for their own good. IMHO, packing anything more into a thinner size would be 100% academic.
Glad I bought the 2012 Air instead of this impractical tech experiment.