Three detachment rules, seven stratagems and seven enhancements, which is more than any single T'au detachment offers.
Expert Fieldcraft (Advanced Acquisition Cadre). In your Shooting phase, when a friendly PATHFINDER TEAM/STEALTH BATTLESUITS unit is selected to shoot, those attacks do not prevent it from being hidden. Your Observers survive.
Integrated Command Structure (Auxiliary Cadre). Kroot and Vespid prey-mark an enemy unit within 12 inches for +3 inch detection range, and Ghostkeel or Stealth units let nearby Kroot and Vespid shoot while staying hidden within 6 inches.
Superior Craftsmanship (Experimental Prototype Cadre). Battlesuit Character units' ranged attacks have +6 inch Range.
And here is where they overlap in a way that is genuinely more than the sum of the parts. All three want the same three or four datasheets on the table. Stealth Battlesuits are named in the first cadre's rule and in every one of its stratagems, and they are one of the two carriers of the second cadre's stealth aura. Ghostkeels carry the second cadre's aura and are legal bearers of the first cadre's Unmasking Suite. Pathfinder Teams are named in the first cadre's rule, all three of its stratagems and one enhancement, and they are what makes the third cadre's extended-range character shots worth taking.
The result is an army where a small stealth core does three jobs at once, and where almost nothing on the board is hidden by accident. In an edition with a real detection layer, an army that plays the concealment game deliberately from three directions is a genuinely awkward opponent.
The seven stratagems are all 1CP, which is worth knowing: no single play in this list costs more than a point, so command points go further than the button count suggests.