Altered Time - your #1 World of Warcraft Mage resource!

After watching a video about saving fire blasts till the last millisec of the blaster master buff during combustion burn I was thinking it would be better, when your in the last 30% of the fight with searing touch, to let your fireblasts stack up to 3 then use them to build stacks of master blaster instead of just using them when available? It makes sense in my head but their must be cleverer mages on here than me .

Yeah. You only do the BM stacking in 2 places; Combustion and Execute since those are the only places where you can reliably crit.