The theory is important, obviously—but the reality of manufacturing a rangefinder camera system can't be overlooked, either. In an ideal world, if production tolerances were perfect magnification versus physical base length probably wouldn't matter. But as it stands, when two rangefinder systems have identical EBLs, but differing quantities of optical magnification—assuming both are built to identical standards of mechanical precision—the one with the longest actual base length will be the most accurate. If it was as simple as magnifying the patch image up to a usable size, camera makers could have designed a half inch base length and simply amped the system up optically. The best did the exact opposite and implemented the longest possible physical base length, knowing that it was a superior approach which would not unduly exaggerate the effects of inaccuracy in the beam deflection, inherent in any mechanical and optical system almost regardless of cost. If you greatly magnify your patch to improve usability you are greatly magnifying whatever tolerances you've decided you have to live with in the mirror or lens deflector, it's pivot, plane alignment, etc, etc.
It seems nobody (well perhaps other than myself) ever mentions the ratio of deflection, either. Put simply the further the patch image travels across its usable arc from infinity to minimum distance, the more finely graduated the adjustment will be. In simpler terms you could think of it as being akin to gear ratio of the system. Less arc = quicker to use and more responsive—more arc = slower to respond but, potentially, far more precise.
According to no less a source than Lipinski. the swinging wedge system used by another first quality maker of rangefinder cameras *in itself* yields an increase in RF precision of an astonishing four times greater than the screw mount Leica. That is even before the gigantic physical base length involved, and the EBL, is factored in. As superlative as it undoubtedly is—by comparison—even the M3 is merely the best of a bad lot. But it's a wonderful viewfinder with integrated frame lines and lots of good features, so that's OK...
EBL is helpful for broad brush comparisons between different cameras. But it does not tell the whole story behind what makes a RF accurate. Not by a darned sight.