Lawyers, as a whole, are total disreputable assholes.
Let me explain my credentials for making that claim: two of my closest friends and roommates are law students, and I have therefore been exposed to the habits, mannerisms, and thought processes of lawyers on a daily basis for quite a while now. And as frustrating as it can be to be proven wrong on semantics, protracted pseudo-logic, or just plain old-fashioned black magic, eventually you have to realize that being proved 'technically wrong' is exactly the same thing as being proved 'regular wrong'.
Let me explain my credentials for making that claim: two of my closest friends and roommates are law students, and I have therefore been exposed to the habits, mannerisms, and thought processes of lawyers on a daily basis for quite a while now. And as frustrating as it can be to be proven wrong on semantics, protracted pseudo-logic, or just plain old-fashioned black magic, eventually you have to realize that being proved 'technically wrong' is exactly the same thing as being proved 'regular wrong'.
One of the most hated groups of 40k players are those soulless bastards known as 'rules lawyers'. You know the type; arguing with you over the definitions of the terms in the rules, exploring every possible interpretation of the written wording of even the simplest-sounding processes and happenings, and bringing a new level of clarity to the contentious and convoluted rules of our beloved hobby.
Wait, what was that last part?
Yeah, that's right punks. I just said rules lawyers are good. Now, this comes with the obvious caveat that taking anything too far is bad; Johnny Cochran is a bit dubious, but not every defense attorney is an unscrupulous prick, yah? Yah.
Break it down with me, daddy-o; we play Warhammer 40,000. This is a game that has rules. Those rules exist primarily in written form, the interpretations of which are obviously dependent on the meanings of the words with which they are expressed. The definition of each word in each rule has to be clearly and consistently defined in order for this game to make any sense. Take, for example, the seemingly simple word 'turn': according to the main rulebook FAQ, this only means a player turn, and not a game turn (two player turns). That's a big fucking deal: that's the difference between a Grey Knight Squad casting Hammerhand in your turn as well as his, instead of just half the time (or him not being able to cast Might of Titan in your turn. Have I cashed in on GK paranoia enough, here?). The word 'turn' could arguably be used to refer to either 'game turn' or 'player turn' based on the fact that both those concepts use the same word, but here we have a ruling that says that only one of these interpretations is correct. Might it not be the one you had personally thought was right? Too bad. In situations like this, the annoyance of arbitration is secondary to the necessity of clarity. In order for games of 40k to make sense we all have to agree on what all these terms mean ahead of time. Even if the FAQ didn't have an explicit ruling on whether the word 'turn' refers to player or game turns, we'd still have to come to a definite conclusion on which one of these definitions is right in order for the rules of the game to be consistent. Is being on the wrong side of one of these rulings frustrating? Bet your corduroy jacket it is. But 'broken' is worse than 'frustrating', and it's because of rules lawyers that we can make that distinction.
Let's take a look at a more relevant and unresolved issue: two of the premier tricksy combos in the Necron codex are using Orikan the Diviner's Temporal Snares ability in conjunction with the C'tan Writhing Worldscape Ability, or alternately using the Tremorstave of the Harbingers of Transmogrification in conjunction with the same. Both operate on the same principle: make terrain difficult, which then becomes dangerous by way of the C'tan's ablility. But even though they appear very similar, there are differences in the wording of the rules used that has to be inspected before we can say this tactic is k-k-k-kosher.
Here's the wording for Temporal Snares (pertinent bits bolded):
"During the first game turn, all enemy units that move count as moving through difficult terrain. If they are actually moving through difficult terrain, then a unit can move the lowest D6 result of their difficult terrain test, rather than the highest."
And here's the Tremorstave, more specifically the Quake special rule that has the actual effect:
"Quake: All enemy units hit by a weapon with the Quake type treat open ground as difficult terrain during their next Movement phase."
Finally, here's what Writhing Worldscape says:
"Whilst the C'tan Shard is on the battlefield, all difficult terrain is also dangerous for the enemy. If the terrain is already dangerous, the Dangerous Terrain test is failed on a 1 or a 2."
Now, what we are tasked with doing (at least until the FAQ comes stomping through) is figuring out which wording means what. One, or both, or neither could be legal combos, and the only way we have to decide is by being rules lawyers. To me, the phrase 'counts as' implies a change to the way the TERRAIN ITSELF is handled. The open ground becomes sort of a facsimile of actual difficult terrain. It takes on the attributes of difficult terrain, without actually becoming it entirely. We still make the distinction that it is really just plain ol' open ground with a funky temporary makeover. On the other hand, a unit that 'treats open ground as difficult terrain' is much different. In this case, we handle the way the UNIT IN PARTICULAR behaves. It treats open ground exactly the way that it would difficult terrain, every time, all the time, in every way and in every circumstance. As far as the unit in question is concerned, the two are absolutely identical while the Quake rule is in effect.
So, we can logically conclude that based on the specificity of the Quake rule, all units that move through open ground while subject to it invoke every single provision of difficult terrain, which includes counting that terrain as dangerous if the C'tan is fuxxing with it.
The more difficult question remains, does Temporal Snares do the same thing? As far as I'm concerned, no it does not. Despite the fact that the wording of Worldscape seems to refer more to the terrain as opposed to the units moving through it in the same vein as Snares, the phrase 'counts as' kills this one in the crib. Open ground 'counting as' difficult terrain is still just open ground. It may mimic difficult terrain, but it can only do so for normal circumstances, and with the normal ruleset for it. I don't believe that any special circumstances imposed by other rules would affect it. It's too much of a shallow, tenuous relationship for Worldscape to lay its hurt on. This is of course just the interpretation of a single deranged gentleman, but until the FAQ comes out or somebody rebuts my argument by threatening to punch me repeatedly in the arm (I HATE that), I'm sticking to it.
In summation, folks, the reality of the situation is that a game based on rules has to have those rules scrutinized and examined. They can't be left open to personal interpretation; they have to be debated and reasoned through frequently if there isn't a black-and-white FAQ ruling to pour some decision-milk into our bowls of anarchy cereal. Ask yourself, as much as you hate getting into semantic debates in the middle of a game, would you rather play a dude who bends rules according to the situation and takes advantage of any available ambiguity? Or an opponent who insists on a strict and clear meaning for each rule and abides by them himself, regardless of whether you're on board with it?
Now, do yourselves a favor and troll me to pieces.