True. I've generally seen halation clearest, though, with things that are highly IR-reflective against a dark background -- where, of course, the IR filter boosts contrast. I've seen this effect (which I sometimes call 'dripping with light', because that's what it looks like to me) more clearly with stronger filtration. An ordinary deep red doesn't seem to produce it as strongly.
And I fully second your comments about enlargement, though there is a sort of 'glow' with Maco Aura even at 5x7 (the only size I have). A lot of these very subtle photographic effects, including the half-tone effect, are visible at levels at which rational analysis might suggest we should not notice them.