The argument doesn't even work on a writing standpoint.
The argument is that there wouldn't be much of a fight to read if Mirajane just easily beats her opponent with Macro....Well, there isn't much of a fight when Gray just beat Mirajane in a fight that began and concluded entirely offscreen. Mashima clearly doesn't care if he makes characters a "one trick ponies" because he makes Natsu use demolition fist and Erza use her katanas all the time. Doesn't bother him one bit. He also clearly isn't concern with padding Mirajane's fights with panels because....the entire fight with Gray was offscreen.
The argument is that there wouldn't be much of a fight to read if Mirajane just easily beats her opponent with Macro....Well, there isn't much of a fight when Gray just beat Mirajane in a fight that began and concluded entirely offscreen. Mashima clearly doesn't care if he makes characters a "one trick ponies" because he makes Natsu use demolition fist and Erza use her katanas all the time. Doesn't bother him one bit. He also clearly isn't concern with padding Mirajane's fights with panels because....the entire fight with Gray was offscreen.
. Mira not using Macro is just CIS, plain and simple. Y'all trying to make hypotheses as to why a character didn't use their hax like it's that deep. It's not that deep. Not doing hax =/= hax will not work. You guys try to discredit hax way too much when the manga tells us that it bust PLs. Rajinshuu, Mest, Kyouka, Seilah, Larcade, Macbeth, Eric, Sawyer, Ultear, Meredy, Makarov, ect. have all shown that hax has trumped PL.