BnS don't have any internal GCD and allow to chain skills non-stop (trade mark of any true action combat) so the better your ms the more skills you can pull off or react to enemy attacks. However, games like WoW, Guild Wars 2 or even TERA are build to allow certain ping discrepancies without creating those abysmal performance differences showcase in BnS videos even with minimal ms differences, someone with 30 vs another with 60, those same numbers are hardly noticeable here.