She didn't attempt any 3Ts or 2Ts in 05-06 season in internationals competitions. She landed 2T (in 3A-2T combination) at Nationals, but it was toe-axeled and downgraded.
She fixed and brought back 3T as a part of 2A-3T combo in the 06-07 season. She landed it cleanly at NHK Trophy and URed it at Worlds (but it was not toe-axeled).
In 07-08 season she included 3F-3T, which was ratified 3 times and downgraded once. None of 3Ts were toe-axeled.
In 08-09 season she included 3T as a solo jump out of steps in the 2nd half of her LP and 'Tano 2T as a second part of 3A-2T combo. All of the attempts were ratified, none toe-axeled. Mao credited the improvement of her 3T to TAT, who reportedly asked Mao to attempt the jump out of difficult steps until she became fully comfortable with it. There was a practice footage on YT showing Mao working on her 2T and 3T (also 3T-2'TanoT, etc.)
Skaters who I noticed toe-axeling: Kimmie Meissner (mostly on 3-3T combos), Mai Asada (2T in combos), Yukari Nakano (2T in combos).
I can't think of any (top) skater who could not land 3T or kept falling on it... Usually it's the easiest jump for the skaters and the one they most often attempt in Galas/shows.