Expression tag video does not do a very good job of explaining the expressions. For example, this question is in the challenge:

Using the expression below, what is the result if Tag1 = 3, Tag2 = 2, and Tag3=1? if({[~]Tag1} ^ {[~]Tag2} > 10, {[~]Tag3}, {[~]Tag3} + {[~]Tag2}) ^ 2

The video says nothing about any of the operators. What exactly does expression language do? References are to the functions in the appendix of the manual. So What? These still do not explain execution of the operators in this expression. By using what I know from C the expression does not evaluate.