Tung Oil Floor Finish

Hey there fellow jocks!
I’ve refinished floors in the past, and feel pretty confident about my knowledge about the process and the materials. That being said, I had a customer of mine stump me this weekend.
The woman will have the floors in her house sanded soon. She does not like the look of polyurethane, or any film finish for that matter. She was also concerned about the off-gassing of film finishes. She told me that she would like to use Tung Oil for her floors. I advised against it for a few reasons:
1. It will take a considerable amount of time to dry.
2. It will take forever to apply/buff out after each coat.
3. The finish will not hold up to foot traffic, nor offer a barrier for dirt/dust.
So I’m asking you folks if my concerns were valid- has anyone ever done this? Can you recommend any non-offgassing finish?
Thanks in advance for your time.