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No recollimation.
With four holes, when its out of focus you'll see four sets of out-of-focus images, these will all converge to a single point as you move the eyepiece through focus.
Try it some time, if you haven't.
BTW there was a point with sub-diameter aperture masks if you are looking at close doubles - sometimes the secondary star is invisible if its buried in the second or third bright airy rings around the primary. By reducing your scopes aperture the right amount, you change the spacing of the rings (wider) putting the secondary in the dark space between the rings.
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