I know that Tim was a good age-group swimmer at 13, and reached national rankings in the 400 free. But being a good age group swimmer is one thing; being an Olympic class swimmer is something else entirely; and being at the top of the Olympic class in international swimming is an amazingly difficult thing to accomplish. But national rankings tend to show a nation's depth more than they show the eliteness of a particular swimmer. I'd be more willing to buy that Tim could have pressed guys like Thorpe if he had reached a point of being #1 in his age group at some point or had set an age group record.
Besides, had Tim stuck with swimming, his compe ive days would have likely been over around the time of the Sydney Olympics. Take the 400 free medalists this year -- Thorpe (22), Grant Hackett (24), Klete Keller (22) -- and Tim, at 28, looks like a greybeard.
Frankly, I'm REALLY glad that Tim chose to pursue basketball. Let's leave the Thorpe chasing to Phelps and Keller.