7th Ed not able to all with self. Possibly not even with own supplement ?

Hello all I have just read in the new rule book in the restrictions for allied detachments on page 122 that it states "All units chosen must have a different Faction to any of the units in your primary detachment (or no faction)". Does this mean that army's are not able to ally with themselves.

Also on page 118 where it defines factions the second paragraph says "in the case of older publications, the faction of all the units described in a codex is the same as the codex's title. In the case is codex supplements, the faction of all the units described in that publication is the same as the codex it is a supplement of".

I know that in the supplement books it states that they can ally with there parent books. But what do we follow the new rule book or what is in the supplements.

What does everyone think

Take a second Combined Arms detatchment. Yeah, you'll need a fourth troop, but it's a small price to pay.

Otherwise, I'd count a supplement book as a separate faction for purposes of the Allied detatchment myself.

My guess is that once (if) the faq's ever arrive, supplements will be using combined arms rules.

The rules are clear. Supplements are counted as their 'home Codex's' faction. Ex. Iyanden is Eldar, Crimson Slaughter is Chaos Marines. Therefore, you cannot take a Combined Arms Detachment of Chaos Marines and a Crimson Slaughter group in an Allied Detachment.

However, nothing is stopping you from taking two Combined Arms Detachments of Crimson Slaughter and Black Legion, or Sentinels of Terra and Clan Raukaan. You can take as many of any mixture of Detachments as you like. No FAQ's are required at this point.

It's on page 118: "there is no limit to the number of detachments a battle-forged army can include". So, for each 1HQ and 2Troops you can include an additional 4 troops, 3 elites, 3 fast, and 3 heavy. Meaning if you have 2 hq's and 4 troops, you may have 0-8 additional troops, 0-6 elites, 0-6 fast, 0-6 heavies, etc. So allying with yourself just means bringing an additional force org from the same codex (supplement to that codex).