I'm no expert, but this guide seems woefully out of date.
My little wizard is only at 60 thus far, so things are probably going to change, but in the sub 60's, here's the thing:
The tank merc, great for other classes, doesn't work well for wizards; it's DPS is much lower than ours, but it can't hold aggro off us so we end up tanking anyway.
The cleric merc, on the other hand, DOES get aggro off us, which is not a bad thing, since it tanks just fine. If we are taking damage, then it heals us, when it heals us enough, it takes aggro and heals itself.
That said... I tank. I tank a LOT. Because in addition to that cleric, I've got much better armor than anyone writing these guides had; defiant or it's quested equivalent Scryer's, means my HP is higher than my old SK's was at the same levels, and my AC is right up there as well. Different AC table means I'm taking more damage than he did...but that isn't crippling
My favorite AA? It's Persistent Casting. Because nothing is as annoying as interrupted spells, and since I'm tanking, reducing that event raises my DPS more than anything else.
The most efficient way to get exp, at least at low levels like this, has been to PBAE: Pull a number of light blue mobs at once, get them clustered together hitting me or my merc, and then use the purple spells, which hit them all simultaneously. Hitting at least three mobs, this is more damage per mana spent than anything else in the ********** and unlike the quadding spells, this isn't limited to four mobs; I'm regularly hitting ten mobs at once, and I haven't even started my actual defensives. Max out CA and CS and my merc should be able to keep me alive with even more mobs on me.