Seeking advice on a single button for dps/hold shiftbutton+same key = all cast heal on that target.

[newbox]

This should work, though is it possible to make one a bit like what Owltoid tried work too.
Something like:
/cast [@target,harm][@targettarget,harm] Lightning Bolt ; [@targettarget,help][@target,help] Lesser Healing Wave

Or something like that.
The only problem I can see is that the master may cast the heal on the targets target instead of the target, since you have to put the targettarget version first so the slaves don't just cast it on the master since they are targeting the master for their targeting instead of using focus, which would fix this issue.
Unless of course, you never change master, in which case you'd just make the slaves have a different version of the macro than the master.
But if your master isn't a shaman and will not have the macro themselves and the slaves will always be targeting the master, then all you need for the slaves is something like:
/cast [@targettarget,harm] Lightning Bolt ; [@targettarget,help] Lesser Healing Wave

Hello there again.
After some trial and error im now using the

/cast [@targettarget,harm] Lightning Bolt ; [@targettarget,help] Lesser Healing Wave

(on the "alts" only)

When i target a toon and hit this key they start healing, well one mauye heal the correct target, usually the others heal themself. I discovered that is i target a toon and spamhit it they will indeed all heal that spesific target (which i wanted).
Dunnu if its possible to have all heal that spesific target with one keypress (would be less stressfull) but atleast im helped for now. I find this macro handy for the xp grinding, when one toon loose a bit of hp a click or so on him is enough to heal him.

Though if someone has other thoughts on this please feel free to post your suggestion.