JessEm Mite-R-Slide Question

While checking around on the web for router fences, I managed to come across a really nice condition old style Canadian made JessEm Mast-R-Fence model #04001 on E-Bay. I actually had one of these fences several years ago, but I ended up selling it & I regretted it ever since. Knowing the quality of these old fences I decided to buy it.

Also, while checking around on the web! I noticed that JessEm recently announced that they'll be doing a final production run on the old-style Mite-R-Slide & after that they will no longer be offering it.
That convinced me to also pick-up a Mite-R-Slide before they disappear.

The instructions for the Mite-R-Slide state to place the large bracket 3-1/2" from the end of the fence!
This basically reduces the effective travel length of the slide unit to the router bit! Is there a specific reason they recommend this distance? The only thing I can think of is the possibility of the slide assembly hitting the fence lock knob while being placed in the stored position.

I'm still trying to decide if I want to build a dedicated table for the JessEm set-up?
However due to space limitations, I'm thinking about trying to modify the extension table of my table saw & install the set-up on the extension table. If I make the saw's extension table a little longer & add a short (10") outfeed style table on the back, I figure I'll have enough room to move the fence & slide all the way back & still be able to position the saws fence in front of the JessEm set-up. I'll still have to remove the JessEm set-up for wide crosscuts & rips. but for a lot of normal cuts I probably won't need to totally remove the JessEm set-up.

Here's a couple of pictures of what I'm thinking about, just imagine the extension table extended about 10" added to the back & 10" to the right.

Doug