The thing is, the foreign earned income is both positive and negative.
First it must be totalled, exchange rate calculated, etc. as foreign income on Form 2555, and this positive amount is included with any other income on Form 1040, line 7 (total wages/salaries/tips).
Then--if you do not exceed the exclusion limit--the same figure is deducted as a negative "other income" amount.
So, really, for tax calculation purposes, foreign earned income = $0.
The problem people are describing with TurboTax is that it seems to be interpreting foreign income only as a negative amount--it's applying the exclusion--without balancing it with the positive amount. That is to say, it is not actually factoring it in as income at all.
So the total income appears to be less than it actually should be.