[waheoo]

It depends on your use case. Some people don't want a huge honking power bank permanently tied to their laptop.

That's the biggest issue with this theory.

If I need a laptop with more battery, why do manufacturers keep getting rid of the option in the name of thinness.

I used to get a full 8 hour day in on an extended ThinkPad battery.

Now you're lucky to get two hours.