MA lowers pH which in turn, lowers TA at the same time. I think pooldv just meant it wasn't a one and done. Add acid, and TA lowers to where you want it. That takes some time and sometimes with many, many additions of MA to get the TA where you want it.
Unless you have a salt generator,or you have extreme pH rise, because of very high TA, you should focus on pH instead.
Unless you have a salt generator,or you have extreme pH rise, because of very high TA, you should focus on pH instead.