The typical flange failure (in crossed spokes patterns) occurs when stress cracks appear at the hole and propogate between adjacent holes and to the outside of the flange. Examination of hubs starting to fail suggests the initial crack radiates from the hole to the outside of the flange and is rougly tangential to the spoke orientation. Once this propogates, the crack between adjacent holes forms. This indacates that the critical and more highly stressed area is the material between the hole and outside flange, which has not been altered in the subject hubs.

Of course, it is possible to reduce the spacing between holes to the point where it will fail first. Brandt suggests a rule of thumb of 1.5X the spoke hole diameter as the amount of material between adjacent spoke holes. However, in a standard hub there are spokes in adjacent holes pulling towards each other, so half the material betwen the holes (i.e. 0.75X hole diameter) is carrying the load for an individual spoke. The subject hubs appear to have at least this much material between a spoke occupied hole and the adjacent unoccupied hole.

The other potential area for failure are the six inner holes. The spacing between these holes and any spoke hole is not less than that between the factory's oval holes and any spoke hole, so this should not be a concern. Also the total mimimum distance between these holes and the two adjacent oval holes appears to be equal to the miniumum distance between two adjcent oval holes, so there should be no concern from this perspective either.

Overall, I can't see any case for concern, unless there are some holes that are significantly off location and not readily apparent in the photos. The basic concept appears sound.