Smart Assist Macro

First make this macro and call it something like Select Assist:

/Variable 1 [%Target]

Now you make this macro called something like Assist Target:

/Select [%Variable1]
/skill Select Target's Target

To use these macros all you do is select a person you want to assist... Click the Select Assist macro ONCE. This person will be locked as your assist target. You then use the Assist Target macro to assist that person until you log out or select another person to assist.

For assist healing you can do something like this:

/Select [%Variable1]
/skill Select Target's Target
/skill {Heal Spell name here }
/Select [%PreviousTarget]

To use this you first lock in another healer with Select Assist. Then you use this heal assist macro automatically heal the person the "main healer" is trying to heal... fire off a heal and then select the target you had before you fired the macro...