...meanwhile, it sounds like the new fence is needed. Thanks for the tip. Rick's accessory looks nice too - you being right about "new tool syndrome". I emailed him and look forward to learning more about what his device could help me do (advanced rationalization technique)
When you emailed me last night, you didn't mention that you were building a box. Even though the MGS Guide does not register off the previous mortise locations, building a box is exactly the type of thing it IS
designed for. From your question (without seeing the FOG discussion here) I assumed you were spacing out mortises in a long row, not building a box.
As for registering one mortise off the position of a previous mortise, this is a practice I tend to avoid, as any error in the placement of one mortise will propagate down the entire joint. Furthermore, any minor error in right/left hand alignment between pins will be compounded (multiplied) by the number of mortises in the row.
Oh, one more thing that was mentioned here that might need clarification to some, is that my guide works with both new dog and old pin style bases. It is not necessary to get the new base to use my guide.
If all goes well, I should be shooting a video of how to use the guide (and several other Festool tools in the process) to build a drawer box this very weekend. I have a friend coming over with a professional video system. <<Fingers Crossed>>