I'm a bit concerned about this use of the term 'normal spacing', as if such a measurement actually existed ...
The spacing between frames varies according to the brood comb cell size, and thus the size of the bees raised within them. So - bees of a 'natural' size (4.9 mm -ish) attempt to draw their brood combs at a spacing of around 32-34 mm., whereas large-cell bees (5.4 mm -ish) will try to draw combs at anywhere between 35 and 38 mm. If you deviate significantly from those spacings, then you WILL experience problems, as this isn't a "one-size fits all" situation.
A few millimetres here or there may not seem very critical to us giant-sized humans, but to insects that are themselves only a few millimetres in size, it's an enormous issue.
LJ