I'm a long time user of the DF500, but I've only used it for smaller components that only need a single tenon. I'd like to use the DF700 for heavier applications, but even with the beefy 14mm x 140mm tenons some joints would still require multiple tenons before I'd be comfortable getting rid of my morticing machine!
So here's the question. Imagine for example you were building a heavy workbench, and wanted to mortice and tenon a 5"x 2 1/2" rail to a 4" x 4" leg, the bottom of the rail needs to be a few inches above the bottom of the leg to give some room for your feet, in other words you can't reference from the base of the leg. In order to replicate the mighty traditional through tenon that I'd normally use, I'd want to use four 14mmx100mm or 14mmx140mm dominoes. Can the DF700 be set up to bore these four mortices with absolute location precision, and if so how?
Thanks!
See, the problem is you're not buying into the system completely. Why would you need a bench like that with an MFT and the Festool system?

The trick would be make sure you're indexing from the same face. Ie, you'd have two side by side on two different offsets from the face. Providing the fence can reach down far enough, you should be fine.
Ie,
1) set depth of fence at 20 mm
- cut two mortices on mark lines (both pieces)
2) set depth of fence an additional X mm down
- cut two more mortices on mark lines (both pieces)