I'm one of those said healers....and no i am not bad imo....and also others i have healed.......
I 'would' love healing in this game if the bars were working well...but as others have said its utterly random and for a game i have looked forward too for sooo sooo long its making me not want to play..........fixes each night that 'fix a visual bug for people not seeing guild tags correctly' is kinda lame to me big time.....this needs fixing as number one as its so so important.
check this thread also if you need more replies to the issue
http://www.swtor.com/community/showthread.php?t=12957&page=13