@evildictaitor: Just one run, and a string with only 5 delimited members. Using .NET Stopwatch. Running both tests consecutively in a console app.
I did change it run each 1000 times and the Split method did take twice as long as the index method. Still, "premature optimization..."
I believe the point of the article was to show how inefficient parsing methods can trigger frequent collections that eventually add up. If you want to see that in action, both 1 and 1000 are off by several orders of magnitude.