It basically calculates which field out of the 3 has the most characters and sets the other 2 to that length.
It does? As I read that calculation it returns the contents of the field with the most characters.
How do you use this field to control the format of your report?
PatternCount can use ¶ to count the number of returns in your report but any calculation that counts characters and returns is not going to perfectly predict the "tallest" field due to the proportional fonts used.