Bard MUST pay attention to their gauge, it's fairly clear the entire job was redesigned around their existence. A Bard that doesn't pay attention would essentially be missing the entire point of the job in the first place.

The split second decision making we have to make to maximize our damage output is pretty insane, and the gauges are also the reason why Bard DoTs got buffed to 30 seconds. It's a delicate balance between deciding whether or not you should throw DoTs on more enemies hoping for more procs, or go into blazing machine gun mode.

Honestly, I feel SB Bard is actually harder to optimize than HW Bard, but failure to optimize SB Bard doesn't result in your DPS dropping as much compared to HW Bard.