I tried searching for the older thread relating to this command but was unable to find it.

After reading that thread i became determined to find out what mod it was that made this possible.
After going through most of my addons i worked out it is related to the quartz addon.
by enabling the quartz addon and the timer module /in works

For those that dont know this command allows you to specify when you would like to emote or say something. ( YOU CANT MAKE IT DO ANYTHING THAT MOVES YOUR CHARACTER...ie automation)

the way this command works is simple
/in (time in seconds) /(emote)(say)

So for example you would use.

/in 5 /say Hi
Which would make your character say hi. Can also be replace by /y etc.

Or we could use
/in 5 /e tells guy to go away
which would cause your character to emote "Pactys tells guy to go away"

Keep in mind you could of added a /targetexact character name to that point and just used /in 5 /bonk
Which would use the bonk emote on that character.

So...now you know what makes it work and how to do it. Have fun making your plays

For a longer example heres one of the first plays that i made

Pactys: /in 2 /say What the hell pact?
Pact: /in 4 /say what?
Pactys: /in 7 /say Stop stealing all the leather man, leave some for the rest of us!
Pact: /in 9 /say ...
Pact: /in 12 /say You know what....fine... Ill wait here while you skin it, then you can take it.
Pactys: /in 14 /say Good
Pactys: /in 18 /say umm....Actually..you can have it.
Pact: /in 22 /say idiot
Pactas: /in 25 /say Your such a whinger pactys...just go back to telling mobs they look fat in the mirror.
Pactus: /in 28 /say I agree
Pactas: /in 29 /say yep...more tanking less talking....go go
Pactus: /in 29 /laugh
Pactas: /in 30 /laugh
Pactis: /in 30 /laugh
Pactys: /cleartarget
Pactys: /in 32 /cry

Have fun