Again, not true, you're allowed to place more than one CS, the rule simply says "no siege equipment spam" and "NOT OK: Creating a weapon rack and spawning more than a few items to block movement". Generally I go with 2 to 3 construction sites per doorway depending on the size. Actually putting down more than 2 or 3 is pretty hard anyway without a weapon rack.
Perfect example of a vaguely written rule.
No siege equipment spam
OK: Planting ladders to get to roofs or walls
OK: Blocking a door with a construction site
OK: Planting siege shields to provide cover from ranged fire
NOT OK: Creating a weapon rack and spawning more than a few items to block movement
You can block A door with A (singular) construction site. So only 1 as I read it.
You can only spawn a few items to block movement at additional doors (very poorly written here, what exactly is a "few" 3? 5? 7? and what if the first "few" were destroyed?). Still only A (single) construction site per door (again, as I read it to apply).
Siege is an absolute clusterfuck of a mode to Admin, and this is the perfect example of why. Even the Admins themselves can't agree on what exactly the rules mean and even when we do, whether or not a situation calls for an
application of that rule is up to interpretation. If a door is double width, that allows for 2 CS right? But its a single door and so only 1 CS! No, its a double wide...
It is little wonder very few Admins are willing to wade into that dung heap. The only thing we can do is discuss it with the other admins online and come to a consensus. EU and NA are separate however, and so even when one group comes to a consensus, it doesn't mean it will be the same across the whole.
Rule of thumb: If an Admin online tells you not to do it, it is against the rules and you need to stop. If they don't, well it may or may not be against the rules. Common sense is what applies in these situations, just be aware that common sense is a nebulous term and varies from person to person.
Ditto to IG_Saints statement that my opinion doesn't represent an *official* admin stance.