I've only recently returned to Swtor after a long break, but after a month now, I've been seeing this happen a lot in GF messages and I think this needs to be said: Stop using "code" for no "first timers".
I get it, you want to run stuff, gets your comms, get your gear, blah blah blah. Its the nature of the game. However, with the announcement of a new expansion some older players are coming back and are out of date, or new players are joining for the first time. If you don't want rookies on your team then flat out say so, you don't need to "code" the message by saying: "Must have 190+ gear", or "Must have Achievements" (what does that mean?).
It doesn't take long to do a explain to ppl what to do, or not to do. Even faster if its just one person, all you need to do is tell them what to look out for and where to/not to stand, OR if you have a voice system, get them in so you can tell them. First timers will never learn unless you let them in the group in the first place and even then they need to know what to expect. Explanations take maybe 5 minutes, tops. Every FP or Ops doesn't have to be a speed run. Heck if its a guild event, you might even get a new member out of it.
My point is, stop expecting everyone to be pro's. And if someone in your group says; "It's been awhile" or "It's my first time" then teach them. There is nothing wrong with slowing down, and the group will be better for it.