I was going to modify this to use a mortise and tenon rather than pauls sloped bridle type joint, and I was curious to if I could edge joint 2 pieces to get stock wide enough. Is it poor form to put a mortise thru the glue line on the feet? Is it poor form to have the legs on either side of the glue line, stressing the center joint?
Could you negate both concerns by edge jointing three boards? You’d have the mortice in the middle board and, if it works aesthetically, you could also have part of each foot contained in the middle board, avoiding much of the strain on the glue line.
For example: You want 12″ but have 6″ boards. Instead of jointing two 6″ boards as 6-6, rip one board into two 3″ boards and joint the three pieces 3-6-3 with 4″ wide feet and a 4″ gap between. The feet then extend 1″ into the middle board and your mortice hole is in solid wood.
Traditionally you would avoid stressing some glue joints, but with modern glues and clamps it’s probably not an issue (assuming a well-made joint of course). Besides, the rail is there to resist racking forces and the weight of the user is transferred straight through the legs to the floor so the glue joint isn’t stressed anyway.