Highline Excel 2013 Class Video 03: How Formulas Calculate: Order of Precedence in Excel

This is the Highline Community College Class, Spreadsheet Construction taught by Michael Girvin: Basic To Advanced Excel.
How Formulas Calculate: Order of Precedence in Excel. Topics in this video:
Parenthesis ( )
Reference Operators: colon, space, comma
Example of colon in range of cells
Example of intersection operator
Example of comma (union
Negation
Converts %
Exponents
Multiplication (*) and Division (/), left to right
Adding (+) and Subtracting (-), left to right
Ampersand (&) (Join operator)
Comparative operators

[excelisfun]

Highline Excel 2013 Class Video 03: How Formulas Calculate: Order of Precedence in Excel:

[roderickmose]

hi Guys, sorry i'm late to the party but i have a query. In the last example, from time 14:00, comparative operator, i noticed that contrary to the order of precedents excel computed the subtraction first, then the addition last! I'm just wondering whats the rational behind the system being able to determine/execute that order which is contrary to normal PEMDAS?