I did Lost Island HM for DVL with shadow 'tank''. Couple wipes on each boss, and the 'tank' is the first one to melt. Also I noticed that I don't get any heal during spiting phase on 2nd boss. I was thinking that this could be healing issue, until I checked the 'tank' gear.... PVP DPS gear.... 0_o
Wipes repeatedly on the last boss, the 'tank' said sorry & left, got replacement tank from a friend guild, a real tank this time, one shooted the last boss