Greg's co-worker really wanted to make sure that a variable was correctly set to true or false. So they did this:

if (isValid == true)
{
	isValid = true;
}
else
{
	isValid = false;
}

If isValid is true, set it to true, otherwise set it to false. isValid is a boolean in C#, so the only options it could have are true and false.

The real WTF is that in languages with truthiness, this code may actually be useful- converting a falsey value to a literal false. But in C#, this is both useless and stupid.