bee space in middle of comb for horizontal hive?

[windfall]

I posted this question last night over in Top Bars, because it's regarding a horizontal hive. But perhaps it belongs here since it uses frames?

I am planning on building a horizontal hive for spring, sized to fit deeps.
As I gather info, many folks have  made claims about increased difficulty in overwintering since the cluster must move to the hive edge to proceed to the next comb. (others have said this doesn't matter). But I must admit it makes a certain amount of sense to this newbie that forcing the cluster to thin out at the cold edge seems like an additional challenge in our northern VT winters.
I came across some folks talking about drilling "communication holes" in through the center of combs in Lang hives to allow bees to jump across. This seems a bit aggressive/crude to me but it did bring another thought to mind:
I was probably going to make the frames for this hive. I am planning to go foundationless. I am now thinking that instead of running wires as as I was considering, That I might add an additional wooden bar running horizontally halfway down.  I can a think of a number of designs that allow me a 3/8" opening 6-8" long in the center of this bar. I had also considered ways to "wire in" a central wooden  "window"
I assume the bees would leave this beespace window/passage open?
Does anyone think it would aide the cluster movement?
Are there good reasons not to do this (other than additional work)... such as breaking up the brood nest?
Essentially I believe I would be making each deep frame into the rough equivalent to two shallows "stacked"