Every once in a while when healing as an attack, your character will disconnect. This has happened to me at most places I've farmed, including voodoos and gobies. I've also noticed that occasionally when healing a party member, that person will also disconnect. Edit: Not sure if MP Eater could be part of the issue? It was brought up in shoutbox, but I use other skills with no problems.
I am having the same problem at GS5. I don't know if MP eater has an effect on it, but as soon as I spam heal for a few min without moving too much, I DC. It doesn't happen on other characters. EDIT: I have dc'd about 35 times in 2 hours just spamming heal at MP3 and GS5. I have to say it is quite annoying. Could that be a contributing factor to dc's in bosses when people bring in Bishops? Since as the post above states, it seems to dc party members who are healed too.
It seems when you do not hold down the button and instead press the button repeatedly(you heal fast but not too fast), it does not dc as much. I wonder if it does the same for other skills of other classes. It seemed to help to keep moving between casts too.
it does happen to other classes yeah. I stopped using haste at krex and now the mules dont dc as much anymore(they do still dc sometimes though, maybe its another skill or krex's skill idk)