I had to look up "AIUI" because I didn't understand your comment, it turns out it's a capitalization for "as I understand it", so you basically made your commen

I had to look up "AIUI" because I didn't understand your comment, it turns out it's a capitalization for "as I understand it", so you basically made your comment less readable to avoid typing 15 characters, which at a modest typing speed will take about 3 seconds to type. So if you've read this far it means it's already been a negative return to type the shortcut.