I do own the parallel guides, and they do serve a purpose but not here....
when I am ripping down a sheet or some long boards - it's one cut in the X direction, then another cut in Y dimension.....
If I have stacked sheets, I could not make all the X cuts with the parallel guides, or I would have to lift the sheet off after the X cut, move it, cut the next one, etc. (and this assumes they are all the same X dimension)...with my system, I slide foam under two sheets layout lines, and make two cuts and have two identical pieces without moving the wood till its at final dimension.
Putting parallel guides on and off the rail would ruin the "convenience factor" of the entire cutting system for XY cuts.
I use the parallel guides when I need 2" strips, and 40 of them, its the perfect tool for that job.... or anytime you need the same width from the same board, many times, its worth setting up the parallel guides.
For me, most of my cuts are different X and or Y dimensions.... of course, sometimes I have a handful of the same dimensions such as shelves, in which case I use one of my first double stack as the measuring stick for the next ones.... ultra fast, and "almost identical dimension"....you might feel the difference with your finger when you align them, close enough for most ww tasks, specially shelves. Anyway, I "cut to the line", and am assured my double stack will come out identical...now the only room for error is proper layout and assuring the bottom board does not slip, never happened yet, and when I am unsure I clamp'em...
Also, when working alone, I find it very difficult to rip 5 ft + boards through my cabinet saw.... why? It's hard to push forward AND against the fence from behind the board. So I often get saw marks on the board from slight changes in force, very fine, but now I need edge treatment, which also changes width... so I must account for this a bit.... with the TS75, the cuts are identical and never need treatment, although I always keep the blades sharp which helps keep the cuts ultra clean. Now, a second person, or some jigs on the TS can change this equation a bit.... but I work alone quite often.
Even going a step further..... I no longer edge join long boards on my 12" joiner, (again 4ft range and longer)...Instead, I lay the rail where it needs to be, and a "single" cut, faster, perfect edge (vs. tons of swipes on the joiner) ..... then, draw a few width lines, mark long rip line, set rail, and cut. Now two identical sized boards of perfect rip dimension .... its the easiest method I have used.... no more changing joiner blades from edge joining, which wears the blade near the fence, making face joining uneven. The rails solve this problem as well.... sort of "joiner blade savers"... :-) Much of the hard wood I buy, needs a lot of edge joining...getting rid of that swipe, swipe, swipe task has saved my wrists, arms, shoulders, etc. as some of these long boards can weigh 40+ lbs...
Thanks for caring Festool :-)
IMO, I don't think the Festool rail system is marketing well....it can do so much, but many people never think of many of the applications.... luckily I learned from a few Festool employees... who are more than helpful. This tips have simplified, improved, sped-up, and have reduced potential for errors in my workflow.... Kudos to Festool tools, AND Festool employees, in this case, its a mix of a great tools and great application of the tools which requires some education....and no, I have not drank the Green Kool Aide... I have lots of tools from many different makers.... When Festool is the right tool for the job, I buy it, use it.....