So how did GE manage to pay no Income Tax?

I haven't checked GE's books, but its probably tax loss carry forward. Under US tax law, companies that lost money last year can subtract last year's losses from this years income.
We ought to rewrite the tax law to do away with tax loss carry forward. Right now, companies that loose money get a a double tax break. Loose money and they can rightly show no taxable income for the year of the loss, AND they can reduce their tax next year by the amount they lost this year.
I don't think we need to reward losers in our tax code. Companies that loose money ought to go out of business, not get a tax break. Companies making money ought to pay income tax on earnings regardless of how bad last year was.
Plus it would surely simplify doing their taxes if they couldn't mix last year's books with this year's books.