Warrior/Warlock combination

I am curious to see how others have dealt effectively with this combination. Currently what I am attempting to do is have my warrior main tank while my lock obviously does dps. My lock's spec is affliction and both characters are 70. As much as possible I am trying to concentrate soley on tanking since that is the most important job. In that vain I have set it up so that as I go through my 5 main tanking skills my lock is casting four dots and shadowbolt. The obvious issue is that the lock reapplies his dots too quickly. My current solution to this is that I have set up, for my warlock, macros such that the first time the key is hit he casts the dots the second time that same key is hit he casts shadowbolt. For those people with more experience is there a better solution?

Personally I would separate out your 5 main tanking skills from the locks damage.

so for example. Bind a key on the warrior that does nothing, but that triggers a castsequence macro on the warlock.

Then get into the habit of hitting the warlock attack key in between your 5 main tanking skills.

e.g

You have your 5 main skills bound to keys 1 to 5.

you would be pressing 1,2,3,4,5

I would suggest binding key 6 to nothing on your warrior but on the lock it triggers your cast sequence

e.g

(something like this - please not the conditions might not be spot on but you get the idea)

/castsequence [reset=24/target/dead] Curse of Agony, siphon life, corruption, immolate,life tap, drain life, drain life, shoot

or

/castsequence [reset=24/target/dead] Curse of Agony, siphon life, corruption, immolate,shadow bolt, shadow bolt, shadow bolt

You would then weave in your lock damage while tanking e.g

1,6,2,6,3,6,4,6,5,6

I'm sure it would become second nature after a while.