Basically, yes it's true. It's pretty insignificant. The right moveset is much more important. Focusing on 100% IV is only what you do when you have the excess. It's less of a focus and more of a perk.
It is true, i makes little difference. BUT considering you're using Pokefarmer and star dust being almost unlimited high IVs are the way to go.
For some brain straining information on IVs go through this youtubers videos. He has some great videos about explaining IVs. Trainer Tips
- YouTube