Back when I was building a lot of strippers I did it more old-school. I learned strip building from guys who were building them for a living and turning out nice finished boats in about 75 man hours, so they didn't have a lot of time to spend sanding. It is quite possible to go from raw strips and glue drips to baby-butt-smooth wood, ready for glassing in 90 minutes or less and do it using half a dozen or fewer sanding disks. Filler coat sanding after the glassing was abother 1-2 hours. Inside sanding took maybe 2-4 hours, mostly because of the uncomfortable working position and the need for frequent rest breaks.
The key is big power and a light touch using big disk sanders. These are my old stripper sanders. The outside wood was sanded in two passes using a 3450 RPM B&D disk grinder (labeled A in the pic). First pass - 7" or 8", 80 grit floor sanding disks on a hard, stiff phenolic backing plate. The advantage here is that it cuts so well that glue drips and other surface junk are cut down like butter. This allows you to concentrate on getting a nice, smooth, non-wavy surface, rather than all the small ups and downs that many people get with smaller, slower sanders as they work over and over on little problem areas.
Pass #2 with the big disk sander used 100-120 grit paper disks, glued to an automotive "feathering disk" pad (the red and blue ones labeled B). This is a stiff plastic plate with a thick foam pad attached to it. This was a quick pass, just to give a finer-grained surface, free of any swirls from the 80 grit. The hull's outside was then ready to fiberglass.
Inside sanding was done using the same sander and floor-sanding disks, but with a 7" rubber back up pad called a "Black and Decker Super Flexible" (labeled C). It can be leaned on as you sand and will bend to some extent for sanding the inside curves. This is, by far, the most tricky part of big-power sanding, getting a smooth interior without cutting too deep. Finish sanding on the inside was done with a 1/4 sheet orbital sander and a soft pad (E).
After glassing and filling, the cured filler coats were sanded smooth with the feathering disk pad and a couple passes, typically 100 grit for the first and 150 -180 grit for the second pass. When we switched from polyester resin to epoxy about 1978, we also had to switch to a slower sander for sanding filler coats. The 3450 RPM sander was literally melting and smearing the epoxy resin. I bought a 1725 RPM Milwaukee polisher for this (D) and later, when they became available a PC 5" random orbit, which despite being reasonably cheap has held up pretty well through several big boat glassing projects (F).
I'm certainly not suggesting that every strip builder sand their boats with big disk grinders, but that's how production builders usually do it and maintain high quality while drastically reducing sanding time compared to home builders. The bad news is that the learning curve is pretty steep. You can make mistakes in a heartbeat with a big disk, and most folks (including me) chop the crap out of their first boat just learning how to use the sander. A combination of plane what you can, scrape what you can and then sand what's left with a decent random orbit machine, orbital or long-board is probably a better bet.