I had the same question about Gross Income from all sources and as usual logic doesn't always apply to the IRS. I would have thought you would add back things like non-taxable state refunds, non-dividend distributions etc. However I talked with a TT Tax Expert and contrary to the many TT representatives that other posters have found terrible to deal with, this person was excellent. Knowledgeable and committed to resolving questions and issues, with many years of tax experience, he explained the IRS definition of Gross Proceeds are taxable items and in my case it meant adding back all ST and LT Capital losses. While time consuming adding up all of my individual Capital losses transactions from my investment accounts, I was able to reconcile the $11.1K difference between my AGI on the 1040 and line 3e on Form 1116. Hope this helps.
