That's complete crap "carb's increase power".
Any engine that is optimised will always be better overall on FI, no matter how it gets there as it is controlled, something the carb can't do anything remotely as well, it was good in it's day and better than some early FI systems, but it's had it's day if you don't need to use it.
And yes I am talking directly from back to back testing of various engines/specs carbs versus FI, you can get the odd gain here or there with carbs, but nothing remotely approaching the driveability of FI.
tabetha