Is StreamReader.Readline() really the fastest method to count lines in a file?

Question

While looking around for a while I found quite a few discussions on how to figure out the number of lines in a file.

For example these three:
c# how do I count l

Answer 1

There are numerous ways to read a file. Usually, the fastest way is the simplest:

using (StreamReader sr = File.OpenText(fileName))
{
        string s = String.Empty;
        while ((s = sr.ReadLine()) != null)
        {
               //do what you gotta do here
        }
}

This page does a great performance comparison between several different techniques including using BufferedReaders, reading into StringBuilder objects, and into an entire array.