Nope. "Wield" means attacking with, hold does not. For example, I can hold two staffs at once by RAW. They are two handed weapons, so I cannot "wield" either as a weapon to attack with. Due to the fact the staff as an implement doesn't require me to hold it with two hands, I can still wield it as an implement and attack through it - despite the fact I can't actually use it as a weapon. Here we see how the RAW completely proves my point. To "Wield" the staff I need two hands if I want to use it as a weapon. I can HOLD it as much as I feel like. To "wield" the staff as an implement, it doesn't matter if I have two hands and so I can happily do so one handed. Here we can see where the clear distinction in the rules between "wield" and attacking with a weapon is different to simply holding it.
So I can hold two staffs perfectly, when I attack with it I am wielding the implement for purposes of effects (like getting the damage bonus from staff of ruin). I cannot use the weapon as a staff, as I do not have two hands but - yep - I can hold the thing as much as I like.
So "Wield" and "Hold" in 4E do actually mean different things. Also the text you quoted is in reference to attacking, where they use the term "wield" and then they put out if you hold two weapons you need to choose the weapon you are actually attacking with. Either way, I am going to talk about the awesome things that I'm doing in my dark sun game and ceasing with this. Feel free to sue wizards for their terrible false advertising.
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So in my Dark Sun game I have planned for the PCs to actually be present both during and in the aftermath of the period where Kalak is killed. To give it a suitably "gritty" feeling and get right into things, I've arranged for the PCs to be in the gladitorial arena of Tyr. They're about to be executed by horrible monsters for affronts to Kalak, a particular Templar and other individuals they've crossed. I've made multiple ways they can get out from being chained up as delicious lunch for the hungry monsters in the arena and in the interest of amusement, the Templar overseeing things decides to just let things run their course.
What happens during this is that Kalak is killed and all hell truly breaks loose all over the city. This suddenly puts the templar in the position where he's no longer quite so invulnerable, as arena prisoners rebel and elements from other city states (even some of the arena's monsters) decide to take advantage of the chaos to make a play for power. This leads of course to the PCs direct escape, having to battle their way through several 3 and even a couple of 4 way fights (though it is possible to ally themselves with different sides if they can be convincing enough). Until finally running down their executioner and giving him a nice hammer or similar to the face.
I then intend to have a "break" between this very combat heavy and fast paced beginning between after Kalak dies and when the campaign begins properly later. The PCs can organize various things they want to do and the players can even change/introduce new characters - the opening of the game is pretty brutal to say the least. From there I am not sure if I want to have a sort of Dark Sun cliche "You are going on a caravan..." sort of affair or not. I have a few ideas, but it would be neat to get them into the desert with a more interesting and compelling reason than that. Then again, it is a very classic Dark Sun element and while I played it in 2E, for most of them I think it's the first time they've played Dark Sun so maybe it is okay.
Either way, I really love the flavor/mechanics of making the environment just as much as an enemy as anything else. So I'm going to emphasize just how horrible and deadly the desert is - even before you throw ravenous undead and psychic tentacle monsters at them.