Then your practicing cognitive dissonance.
Which actually explains a lot.
-=Edit=-
I'm not arguing whats best, it's obvious that a WHM with an enhancing set is better then a WHM without one. Just like a WHM going /SCH is better then a WHM going /BLM (/RDM is up in the air).
I'm arguing what's actually being used. Theory is nice on paper, but it's what happens in reality that gets things done. And from every observation /BLM is the predominate sub because of the quantity of D2's that need to be passed around after each fight. Their doing it to speed up travel between fights.
Just like the enhancing set above, I do agree that a dedicated hard core WHM can go out and with lots of work get this insanely awesome enhancing magic set. But what on earth would they use it on? Closest thing is barspells, but we already know the resistance is crap, your really using them for the MDB / MDC effects. And even then, these days having a WHM run into range of the tank during a NM fight usually means BBQ'd WHM.
Now if WHM could target those spells onto someone else, then we'd be talking differently.