This is something that, as a current player, concerns me quite a bit. I can live with any other part of my body getting fucked up, really.
I don't know how it's being run in Ireland, but the RFU highly recommend doing a baseline assessment on all RFU registered players (those playing first team rugby).
Here's the tests that I've had to perform, the so-called Scat3 test:
http://www.englandrugby.com/mm/Document/MyRugby/Headcase/01/30/49/37/scat3_Neutral.pdf
The immediate memory, delayed memory and concentration tests aer hard to get 100% right on a normal day (think I got the last digits backwards test wrong...) so you can clearly see, there's a pretty decent test of how the brain is actually functioning.
Thing is, you can learn the standard responses, and be able to rattle them off whether or not you're concussed.
That's fucking stupid behaviour by any player, but you can't legislate for idiots undermining their own safety.
Followed properly, I think I'd pretty confident that test would pick up concussion pretty reliably.
Any health professional deciding not to bother with it, any player deciding to game the system or any coach deciding to ignore it should, IMO, be banned (and in the case of the medics and coaches, criminal prosecutions for reckless endangerment be brought).
I think rugby has recognised there's potential for problems here, but I'm also pretty confident that those problems are now being properly addressed. If a player at a club six divisions down from the English premiership is being baselined and monitored using these guidelines, then I see absolutely no excuse whatsoever for not having the same for the pros.