This comment is not scientific nor have I ever had my truck on a dyno for before or after. But let me say this...
When I put the bigger intercooler on my truck, I "felt" throughout most of the RPM range there was more power. Stock trucks may have plenty of fuel, but the air can be improved, more so as cooler than quantity I think. But I always felt powerband leveled out sooner than I thought it should.
When I put bigger fuel lines on my truck, I "felt" that the second half of the RPM range liven'd up quite a bit.
Again, this is "feel" not proven. I request that someone who sells the idea of bigger fuel lines do a before and after on a dyno and publish the numbers. Same for those who say drilling out the banjo bolt is sufficient for tuned only trucks. A before and after on that notion would be a 5 minute job between runs.
Perhaps that will settle the issue with science rather than bravado and bickering. I for one would think this data is already on someone's desk as I can't imagine someone would just sell parts to sell parts.
Let's see the numbers, at least for the sanity of those who have trusted the sales pitch and installed these bigger lines.