the man can and should share his feelings (if he has any) and that it is healthy for the woman to consider those. For example, if my wife were hell bent on doing a home birth, I would express great concern over the risks and push for a natural birth with a midwife at the hospital. But at the end of the day, I couldn't force my wife to do that.
I think it's fine for the husband to even weigh on things like whether she gets an epidural, but I wouldn't push too hard on those smaller things.