T7 is the turn most groups have an issue with when there on farm. Its long, there's lots of downtime if your DPS is good and really even a small mistake is game over. My group generally stops all non essential chat in that turn just to maintain focus.

Based on your T8 issues though you may want to look at your group. Its probably the most straightforward fight in SCOB. If your still wiping to silly things after a clear you may have an issue. Its tough to do but if you have a consistently inconsistent player you may need to consider a change.