This is essentially the Ammo+ variant of the Brawl build with Flamers instead of Medium Lasers. The idea is to get close and limit their DPS while pumping out damage. Edit to add: This build doesn't have the speed to make flamers useful most of the time. I played several rounds in it before I finally made it work. When it works: it is glorious. You can 1v1 another assault and barely get scratched. However, the MLs offer a lot more midrange punch (especially at the 270-350m range where they're still pretty effective, but your SRMs are useless). I've had 900+ damage multiple-kill rounds in both versions. While this is potentially more fun, the ML is probably better.
Why Flamers instead Lasers? Why 4 of them?! I never had Fun with Flamers bcoz you can't kill Mechs in MWO fast enough with Flamers. Check Up the Fun with Flamers in MW2:Mercs