Actually, I mentioned that tactic in my post about my Githzerai Monk...although it was with psionic Enlarge, not the arcane version.
As for the Monks being allowed to take INA question being "official", WotC has published at least one Half-Orc Monk build with INA (in PHB II, p51) . That, I would think, would put to rest the "officialness" of the opinion...except that for whatever reason, the Monk in question 1) is first level, thus does not have the +4 BAB prereq, and 2) is first level, thus has one too many feats- 3 instead of 2. Still, obvious errors aside, at least one person who worked on that book considered it official enough to contemplate it for the build.
I've said this of WotC and other publishers as well- those guys really need some better proofreaders, perhaps even some Continuity Editors!