Yes, you can capsize an AI or TI in the right conditions, even without an ama/aka malfunction, don't let anyone tell you otherwise. The AI/TI is quite resistant to capsizing (once you've made the necessary modifications), but any small sailboat can capsize in the right conditions and it can happen quickly. A capsized AI/TI requires practice and skill to upright, especially in rough conditions. Be sure to watch
this video.
The trick is to try to never put yourself in that situation by planning ahead for all circumstances and acting accordingly. Here are some tips I've learned along the way, sometimes the hard way.
Know your limitations, if you're an inexperienced sailor, don't go out on days with small craft warnings. Until you learn the basics and the boat, don't sail in wind conditions exceeding 10-15 knots. Give yourself plenty of time to learn in milder conditions. Take a sailing class if available. If not, read as much as you can about basic sailing. The AI/TI are one of the easiest boats to sail and to learn to sail on. But take it slow and safe at first.
Don't sail too far out from shore or from your starting point. If the winds change or conditions deteriorate, as they often do, you may find you can't get back before dark. Always plan your day trips with plenty of room for error at first. If you blissfully sail for several hours downwind keep in mind it may take you much, much longer to get back upwind. You will soon learn your range and can then safely explore further.
You may find yourself suddenly in stormy conditions with high winds and strong waves/currents, even on a day where a storm wasn't predicted. If this happens, get to the nearest safe shore immediately and wait it out, don't try to make it back in conditions exceeding 15-20 knots until you are an experienced sailor. Furl early if the winds pick up. Don't wait. It can be very difficult to furl the sail as the winds get stronger, especially if you're inexperienced.
I always suggest that the safest option you can add to a TI/AI is a motor. A gas or electric motor makes an excellent backup to any small sailboat. If you find you've gone too far out to peddle back after the winds unexpectedly die down, or if you're trying to get back against an unexpected strong headwind or current, the motor will get you safely home. If you find yourself unexpectedly in high wind conditions such as when the winds pick up more than predicted or in a storm, you can simply furl the sail completely and let the motor take you back to safety. Once the sail is fully furled, the chances of a capsize are remote. In this forum, this is called "Get out of Dodge" mode.
I've owned my TI since 2015 and I've been in all of these conditions and more. The majority of the time I feel very safe, but there have been incidents that gave me a far greater respect for nature. I once almost capsized in a storm in which I'm not certain I would have survived. The Hobie AI/TI are very safe, well-made boats and there is no need to fear them, but like all boats, they have to be operated safely within their limitations, and that's the full responsibility of the captain. Nature is an awesome force, never underestimate it. Respect it and always be prepared.