how many people have you met in aikido (that have only studies aikido) that can deliver a good solid punch
Um, I'll ignore many of the posts as I'm not sure what they're arguing. Which may show my lack of patience and I may receive grief as a result, but what the heck...
I can deliver a pretty solid punch, but... I had prior training in other things. However, I also teach a few classes and I will occasionally take some folk and work on their punching to make them more solid. Fixing their stance, trying to get them to not over-commit, trying to teach them how not to break every freaking finger in their hand should they ever connect with something solid, etc. It wasn't really part of my Aikido training as in the sense of a sensei taking me aside and teaching *me* to punch (again, I already knew how fairly well), but my sensei would sometimes ask me to go work with others to help them improve theirs.
I've taken focus mitts to the dojo (might do it again today now that I think about it) to work with students. I find teaching them combinations sometimes helps them develop a bit more speed and control as you can't just "lunge" after the first and expect to be able to deliver the second. Personally I think it adds to their value of training in that they learn to attack better but those training with them learn to better deal with a more trained attacker. Frankly I don't mind training with someone who doesn't punch well since most folk out there in the "civilian world" are fairly incompetent. But I like to train with those who can also punch better with power and control as well to improve my training.
If your question is whether Aikido teaches a solid punch, well, that's a silly question in that I'm sure many do not and many do as part of their training. And it would depend a great deal on where you train and who you train with and how focused they are on that kind of thing. We had a guy train with us for a while a few years back who has since gone on to become a great independent instructor (in his mind and PR at least). The guy couldn't punch his way out of a wet paper sack IMHO. And couldn't deal with any punch that could. He was obviously quite uncomfortable with any "serious" attack and he'd often fall back on saying that it wasn't training with a proper aikido spirit. I beg to differ, but whatever floats your boat.
So I'm not really sure what you're asking or what the implication is. But yes, I've met some folk who can punch fairly well and who've only done aikido as I taught them how to. I'm sure others have as well. Lots of us cross train and most O sensei's students came from other arts as well. So most of them could probably deliver a solid punch and I've met students of those guys who could rock my world pretty well if they wanted to. But as a formal part of training? YMMV.
Other than that... Shrug.