I have nothing whatsoever against Mr. Reeve, in fact I liked the man immensely. I only mentioned him because he was the first person that came to mind that everyone associates with a terrible riding accident. I don't follow much TV and none of the magazines I read regarding that incident went into detail about it and so had no idea what really caused the accident and did not mean to imply that he was incompetent--it was a tragic accident which could have happened to anyone. Like I said, I mentioned it because Harry would have heard of it and it would have made an impact upon him. Severus mentions the fact that one could become paralyzed from a fall without a helmet because he wishes to impress upon Harry to always wear his. I personally know someone who DID almost die from not wearing a hat while jumping a horse, but since neither Severus or Harry are horse people, I didn't want to go into details with it. 

I also was not aware that his wife died either.  May they rest in peace.