Understand this but...
that is nothing more than bleeding the brakes. Many manufacturers recommend to flush the brake system every two years. Flushing in my mind is to remove all the old fluid and replacing it. I'd like to replace all my ATE natural fluid with ATE blue but not so easy to get the color that comes from the can out of the bleed nipples
so you KNOW it has been replaced. If the incoming line in the caliper is near the bleed nipple the fluid just does a turnabout and goes out again. I'd like to replace it all in my 190/5.6 before the next track event.
I've made my own bleeder using some 3/16" vinyl tubing, a clear jar with two nipples on top and a AC vacuum pump. This way I just suck it through the bleeder from the master cylinder and make sure no air gets in. Works great for the clutch fluid and other vacuum projects.