One of the advantages, perhaps, of learning directly from someone else is that you can copy their methods until you find the genius in them or you find them wholly unsuitable to the way you do things. I have no formal training in woodworking beyond shop class in high school, so I end up learning mainly from books, tutorials and trial and error. Sometimes this is the long way around, but I generally have the luxury of time.
The last time I cut breadboards it was on a relatively small piece (my Dutch tool chest lid) and I worked the rabbets down with a shoulder plane and jack plane. It worked, but it wasn’t something that I felt would be all that efficient on a larger piece like the trestle table. I wanted to try something different.
There are probably any number of methods to remove this wood and leave a nice working surface. Sawing it out like a tenon is not viable, so it has to be some other combination of edge tools. For a moment I thought of knocking the rebate out with a chisel (Richard McGuire style) but I’m not that brave (yet). And then it occurred to me. Instead of starting at the shoulder and working out, why not start at the end and work in with my rabbet plane? The only downside with this method is that unless you have some freakishly large rabbet plane (like the LN low-angle jack rabbet I’m lusting after at the moment) you can’t do it all in one pass. You can however, work a nice solid rabbet to your lines and set yourself up for round two.
Careful markup goes a long way here. Before I could get to the rabbet plane, I started by marking out and running a 1/4″ groove down the middle of the breadboards. I used the same mortise gauge to strike lines all the way around what would eventually be the tongue. I then clamped the breadboard to the table top like a batten and sawed out the shoulder with my tenon saw.
After running the rabbet, round two involves some chisel and mallet work, knocking out that last 3/4″ to 5/8″ of material between the rabbet and the shoulder. This is quick work and depending on your level of comfort, it can get you pretty close to the finished dimension.
Following this up with a shoulder plane or rabbet plane (without fence or with the fence removed) leaves you with a nice, level rabbet. Repeat on the other side and you have a tongue that requires only minor adjustment when fitting.
The usual caveats apply. Be careful to keep your rabbet plane level. Be careful working to the line. I also left the tongue just a hair thick so that I could shave it down when fitting if need be. I don’t know if this was any faster, but it certainly gave me the results I was after.