Time is relative, but given the surface left from a good smoother (and a scraper if employed) is "ready to finish", one needs to consider all the time "not spent" sanding. I will most certainly employ this method for fine furniture projects based on the results of this project.
That said, between the aches and pains in my hands, arms and shoulders from the plane work and the aches and pains in my thighs, calves and ankles from the equestrian stuff...I'm a walking advertisement for analgesics...LOL