Let me try to simplify the T/A lowering procedure. We've batted this around for at least a half-dozen years until Chem_Geek untangled it so we all understood.
1) T/A reading depends on the pH reading. So at 7.0 you'll get a lower T/A than at 7.8, when actually they are linked. If you raise pH with Borax or Soda Ash, T/A goes right back up.
2) So you lower pH to, say, 7.0.
3) Aeration RAISES pH! The fancy chemistry has something to do with breaking down carbonic acid in the water but the end result is aeration raises pH but does NOT raise T/A with it, unlike other ways to raise pH.
4) You then lower the pH again, pulling down T/A with it, and aerate to raise pH without raising T/A again.

In other words, you are ratcheting the T/A down. The aeration doesn't lower T/A (though if you keep pH constant at 7.0-7.2 it will SEEM that way). Lowering pH lowers T/A and aeration allows pH to rise without raising T/A.

On another note, you keep wasting your chlorine reagents doing the 25ml test. Only do the 10ml test. We/you don't need to know that FC is 7.2 or 7.4, 7.0 or 7.5 is close enough. Same for CC.