I have some questions, and helpful answers would be appreciated
1) In 6th edition, I could ally any army with itself, allowing me to have 3x HQ from the same codex in one army (or 4x heavy, 4x elite, etc.). Is this still possible?
2) If it's possible, how do I do it with Tau?
3) If I take a formation, do the units in a formation count as units in a detachment? For instance, can I take a Firebase Support Cadre for its beneficial rules, and do those 9 broadsides and 1 riptide take up 3x heavy slots and 1x elite slot in my Combined Arms Detachment?
4) In the situation in #3, can the units from a formation be spread across multiple formations and/or detachments?
Thanks!