Not quite the same as baked spuds in the oven, but you can saute small ones until the skins are browned and then put them on the trivet to finish cooking with a little water beneath.
Like the other poster above, I prick large spuds with a fork, roll them in oil and salt, then microwave for 5-10 minutes (2 large spuds). I then finish them in a hot oven to crisp all over, usually about 20-30 minutes.
It's a bit of a myth that everything can be done successfully in an IP. It's a great gadget, but it has some limitations by its very design. I've seen folks online try to convert every recipe under the sun and it seems like some kind of challenge to them. I just work with its strengths and I'm happy with what it does best.