As long as there is NO drag when clutch is fully engaged, it's fine. As the clutch wears, engagement height will gradually come up. That's the way they work.
The clutch does it's own adjusting as needed. The difference you are feeling is the fact that there is a whole brand new clutch under your foot. Used properly a clutch should last the life of the car and never need replaced. I put 350k on a truck(toyota) and never had any clutch work done.
Yes, it is OK, what the mechanic said. With a g35, the clutch adjusts itself, since it is hydraulic, and cannot be adjusted.
I have a 2006 g35 stick shift. I had a new clutch installed, but the car is ready to accelerate when my foot barely leaves the pedal. My mechanic said that's just how new clutches are. Is that true?