Why is OfType<> faster than Cast<>?

Question

In answer to the following question: How to convert MatchCollection to string array

Given The two Linq expressions:

var arr = Regex.Matches(strText,          


        

Answer 1

Actually isof() first checks the type and then casts it, where as cast() just does the 2nd part. So obviously isof() will be slower than direct casting

http://codenets.blogspot.in/2010/06/cast-vs-oftype.html