I guess everyone is different. I was mid 20's and was playing a sort of paintball-type game in the woods. I tripped and did a forward roll. The problem was that I rolled right on a rock and it hit my collarbone exactly right. My collarbone snapped in two right in the middle. The left side went down and under the right side. Or maybe the right went up and over the left.
I never knew that it had broken, let alone in two. I kept going and playing until about an hour later. I found my cousin and said I had this weird bump on my left shoulder. He looked at it and said he didn't know. So, we went to the hospital. I saw the xrays. They gave me a brace and sent me home.
I used the brace for a day. Not that I needed it, but because I saw the xray and thought maybe the bones would shift. I realized that if the bones didn't shift from after the break in the woods, they probably wouldn't shift.
I suffered no pain, no loss of arm function, no discomfort, and it never hindered my aikido rolls and falls. Everyone is different.
I have to laugh every now and then when I hear martial artists say to break someone's collar bone because it'll make that arm useless. I'm proof that it won't always work like that.