Im assuming the OP wasn't there during stormblood when IR halved your gauge spenders so actions like FC, upheaval and onslaught (which used to cost gauge) would mess up your meter and alternatively your rotation if you did not do things perfectly because you might end up with 5/100 gauge at the end of your burst.

No thanks.

However, I am open to the idea of gauge spenders affecting defensive cds. ex. SiO shield effect increasing by 1% for every 10 gauge (in addition to its current effects), ToB increased to 30% HP when 50 gauge is used, Damnation applying fracture when counter hit procs, etc.