OP, this person knows what they're talking about. One of the screening questions when I was diagnosed with ADHD had to do with clumsiness. My own parents used to call me, "An accident waiting for a place to happen."
I have slowly been able to improve my clumsiness a little bit, by exercising regularly with a trainer 5 days a week. One of those days is a balance-focused day and after 2.5 years I'm actually able to hold poses and (mostly) stay upright and steady. But it was SLOW going.
The night before my 50th birthday, after I had been taking this class for 7 months, my husband and I were on a sunset cruise and his phone fell out of his pocket and over the side of the ship. I reached out with one hand and successfully caught it. THAT KIND OF THING NEVER HAPPENS TO ME!
I celebrate that day every year as much as my birthday now. I managed to show off hand eye coordination before I was 50!
Get screened... :)