So there was a lot of back and forth in 5th Edition over the years regarding any Chimera's purchased for a Platoon lead by Al'Rahem. New Edition hopefully means new clarity. Please let me know if there is a flaw in my logic here:
Stalk the Enemy Codex: Imperial Guard, page 64
Any unit that is part of Al'rahem's Infantry Platoon must Outflank.
Outflank Warhammer 40,000 Rule Book, page 40
If such units are picked from their army list with a Dedicated Transport, they may Outflank along with their Transport but if they do they must move onto the table embarked within it.
So, we can definitely Outflank with the Chimeras. That doesn't seem to be in doubt at all. But do the Chimeras count towards how many units can be held in reserve?
Reserve Warhammer 40,000 Rule Book, page 124
When deploying their armies, players may choose not to deploy up to half of their units (rounding up) keeping them in Reserve to arrive later.
Units that must start the game in reserve are ignored for the purposes of working out how many other units may do so. A unit and its Dedicated Transport are counted as a single unit for these purposes.
Independent Characters count as separate units regardless if they have joined another unit or not.
Dedicated Transports Warhammer 40,000 Rule Book, page 78
Sometimes a unit entry in a Codex will include a Transport option, allowing a vehicle to be selected together with the unit.
These Dedicated Transports do not use up a slot on the Force organization chart (see page 109).
Dedicated Transports Codex: Imperial Guard, page 99
These vehicles do not use up any force organization chart selections but otherwise function as separate units.
Transport Option Codex: Imperial Guard, page 97
The squad may take a Chimera as a dedicated transport (see page 99 for points cost).
Infantry Platoon Codex: Imperial Guard, page 96
Composition: 1 Platoon Command Squad, 2-5 Infantry Squads, 0-5 Heavy Weapons Squads, 0-2 Special Weapons Squads and 0-1 Conscripts Squads.
Each Infantry Platoon counts as a single Troops choice on the force organization chart when deploying, and is rolled for collectively when rolling for Reserves
That seems to be everything relevant to the question at hand as far as I can tell. So the question:
For Al'Rahem's Stalk the Enemy, do Chimeras count as part of his Infantry Platoon?
Disclaimer: I want the answer to be "yes". I suspect the answer is "no". If the answer is yes, they aren't counted when determining how many units you can Reserve.
I can see the Dedicated Transports entry on page 78 of the
BRB hinting at the answer being "yes". Nothing seems to contradict this. At the same time, nothing seems to explicitly say this either. The
FAQ was updated and doesn't say.
My argument is that the Infantry Squad is chosen as part of the Infantry Platoon. So the Chimera, being selected with the Infantry Squad, is part of the Infantry Platoon. I suspect I'm reading too much into this and that it simply means it doesn't eat a Force Organization slot. I suspect that its the Infantry Platoon composition that finally does the idea in, and Chimeras then count towards the limits on your reserved force.
I'll admit that I'm doubly biased as I have an Army List idea that hinges on not having 3 Chimeras count towards the total. Nothing has been purchased yet so no real harm to me if the consensus is that they count. I'm prepared to be disappointed so have at it!