The advice won't work with Hollow doors. It won't work right for panel doors either. It might seem like it would but the problem is the person giving such advice doesn't understand the anatomy of doors especially the issue of the joinery of the stile and rails. Dutch Doors are two half height panel doors one over the other.
Panel doors frames are made of three main constituent parts: Rails, Stiles and Panel(s). There are other parts but they are not what I would call the key parts but may still be important. The Stile and Rails are key. Panels are infill and maybe wood, glass, or even a bit of both. The Stiles and Rails are typically joined using a tendon and mortise connection. You may not see it from just looking at it. If you saw through that middle rail, you would ruin the tendon and mortise connection. These middle rails may sometimes be wider than the top or bottom rail but so is the tendon and the mortise pocket as there is still usually only one tendon and mortise on each side. For it to work, the middle rail would have to have two separate tendon and mortise pockets on each side and then be lucky to saw a straight line at the right spot. It is not usual to ever see the middle rail of a panel door (if there is one on the particular door).
The only doors that this media advice is good for is a single piece solid wood door (not panel doors or hollow doors aka hollow-core doors). Single piece solid wood doors are heavy. If they are lighter than a panel door or weights as much as a hollow door than it is not a solid door and is probably a hollow door. Solid doors are heavier because it is a solid piece. Making a door out of cross laminated plywood to a thickness of a door could potentially work in similar fashion as a solid wood door.
The advice given on this media site is dangerous. Not so much for life, health, safety and physical welfare but it is that it will cost people money because following the advice given by this media site is likely to ruin their door because the DIYers out there are usually not educated on the types of doors and because it sounds easy they do it all to find out they ruin their door they spent several hundred doors to purchase. Demographically, DIYers are not professionals and some portion of them are not intelligent enough to know they are not professionals and they will go at it with excitement just to ruin the door they spent a bunch of money on.
Word of Advice to DIYers: Don't Follow this media site's advice of just cutting a door in half. You can end up with more problems plaguing you years to come constantly. Do yourselves a favor and study up and understand the mechanics and principles of tendon and mortise joinery and the anatomy of doors of different types. There are books on this topic with illustrations. This would give you a sense of how doors are made. It is better to buy a book and learn this then learn it the more expensive way through destroying something you spent a health chunk of money on. If you got a door at a garage sale for a couple of bucks and you disassemble it to learn how it is made or destroy it... ok. if you intended that to learn from but if you bought a door at regular store price including regular on sales price... that would probably not be a wise use of money. There are better ways to get the knowledge you want to gain from it.
Brenda, if you like to forward this to the site, be my guest.
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Richard Balkins, Assoc. AIA
Building Designer / owner
Richard W.C. Balkins, Building Designer
Astoria, OR
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