Our progression team has gone through plenty of healers. We seem to be plagued by the type that do okay on the charts, but are "too tired" by the end of the raid night to properly pay attention to boss mechanics, or don't seem to hear something the first time it's said (i.e. "Wait, we're doing heroic Domo tonight?" when it was mentioned several times before). Perhaps your problem isn't that you were on the bottom of the charts, but that you had a similar issue to the healers we've fired.
For the record though, we don't g-kick people. We just let them know they're not on the core team any more... they choose to stay or leave on their own (so far, nobody has stayed).