My son was born 5 weeks early too, on April 30th! I can't help with the infrequent poos, though. He goes about 3-6 times a day, and some of those stretch over a few diapers/pottytunities. It's amazing how different babies can be even this early.
I wonder if he's just uncomfortable in the position that you're using to try to pee him. I was uncomfortable when I was using the classic "in arms" position, so I think that made my baby uncomfortable. I felt like i was going to pull him apart at the legs. Once we found a potty seat that he could sit down on, it got a lot better. We can look at him and talk and sing, and we support him since he can't sit up or support his head all the way. We've been inventing potty songs, which keeps us entertained. I don't think the baby cares too much, but it's fun for me!
His most common pee cue when he's not nursing is "hunh hunh hunh hunh hunh". It's pretty quiet, almost like panting. Then, if we miss it and he wets his diaper, he yelps. If he's nursing, I take him to potty every time he pulls off unless he falls asleep. Then I let him sleep.
You say you're concerned about doing the stimulation and then being right over the potty. I think just try to stimulate him on your changing spot and then move to the potty. Maybe make sure you're not over carpet in between, or lay a towel down. We never have poop accidents between the diaper and the potty, but we do have them between the potty and the diaper if I pull him off too soon. That has happened a few times this week. Fortunately, I saw it before I stepped out of the bathroom and onto the carpet. And then we just head back onto the pot. He will sometimes tell me if he's not done (by crying out when I pick him up off the pot), but not always.
I think I'm realizing that the one predictable thing about this is the unpredictability! These babies are changing and learning and growing so much every day. So we just do our best and laugh when we get pooped and peed on. My husband was giving the baby a tub bath the other day and he starting signaling him that he had to pee, but he was thinking the baby was communicating abour the bath. So he picked him up and got peed on right on his chest. :-) Of course, we always say, "good job!" so that's what we did.
Emma, congrats on your sucess! It sounds like you are doing really well. I would love to be part of a chat thread for our close in age babies.
-Kathy First time Mom to Son F, born April 30, 2009.