It's hard to tell without seeing you swim, but if you feel you're rolling with good alignment, and in balance, yet your ability to get enough air is inconsistent, my guess is that your roll to air may be a bit too tentative? The answer seems self-evident - you're not taking your mouth quite far enough.
There are two possible answers to that:
1) Energize your rotation to breathing. Use the energy of the arm spearing forward to take you to air. For a left breath, it's the right arm spearing to full extension that propels you to air. Tune in to this dynamic
Right arm spears forward . . .
Moving left shoulder back . . .
Follow left shoulder with your chin.
2) Body rotation by itself isn't quite enough to clear your mouth. After you've completed rotation - OFF your stomach, but short of being ON your side - your head needs to roll a bit farther independently. And following the breath, your head will start the return a moment before torso.
Try these and let us know if it makes a difference.
Head Coach & Chief Executive Optimist
May your laps be as happy as mine.
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