with correct gearing and fitness you can spin up most climbs in whatever exertion level you choose. You can cruise up it in z2 endurance or attack the full distance at z5. But with a 1200 ft climb, you can't climb it in z5, you'll pop.

If I had that commute with a shower at the top, I'd be in heaven. z2 today. z4/z2 intervals tomorrow, z5/z2 intervals the next day, and within 3 months I'd be killing everyone (bros, not pros) on just about every hill.