I do that almost every trip, just because I like to fly the plane.
What's really interesting is to have someone do this for the entire arrival. Climbout is pretty easy to do that. The arrival and manually computing descent points, crossing restrictions, etc without auto-throttles and the flight director is what would bite someone who has lost some hand-flying skills.
Flew with a guy last year that freaked when the A/T were deferred, wanted me to fly the whole day. Really? And you're the Captain? WTF? I'm sure most of our guys would be fine, but seriously?
We also have a procedure in and out of SNA that if the A/T are deferred, you have to call Dispatch to get a briefing. They know how to use our Autothrottles? And why does that necessitate a briefing? Pretty dang simple, set Takeoff N1 manually, at 600 feet lower the nose and reduce to cut-back N1, at 3,000 feet, manually set climb power, clean up, and motor on. What's the BFD?
Oh well, I just fly 'em.
If someone sitting in a cube decides it's a BFD, then it's a BFD!