Addon Question / Is this possible within WOW

Not sure if this is possible or not & looking for feedback before I start digging into lua scripting. I have seperate macro's for each of my toons, & several of my friends for things like:
/target Playerx
/follow Playerx
or
/cast Chain heal target=Playerx

what I want to do is build an addon or script that would do the following
A user would type the following
/mbheal1 quix
(the addon would assign the text quix to a variable something like "variable1" or whatever)
then later on a hardware press on a certain key use that variable in a macro format like:

/follow variable1
or
/target variable1
or
/Cast Chain Heal target=variable1

is something like this possible?
The whole point is to cut down on having to manually edit 4-8 macros every time I change a live healer, or change my "main" as I swap groups around.

I am not sure, but I doubt it.

Certainly at my level of coding for wow, I would be unable to do it. Targeting functions are protected and so there are restrictions on using them. However look at what the author of trinity bars 2 has been able to do with that mod, all within the protected framework. So perhaps it would be possible.

This is my dream functionality. You could use a shared variable for determining your lead character and free up both focus and target for other actions.

If you use standard Blizzard macros (rather than Trinity or BindPad or something similar) you could create an external app that rewrote your macros for a specific party set up from templates, you may even be able to do this in game as I am fairly sure you can create macros with lua scripts. I was going to do this myself but as I use Trinity and there is no defined file format or guarantee that the format will not change on a regular basis I decided it was not worth it.