# Notation, Section 1.3.2
-When register operands (`RA, RT, BF`) are prefixed by a single underscore
-(`_RT, _RA, _BF`) the variable contains the contents of the instruction field
-not the contents of the Register File referenced *by* that field. Example:
-`_RT` contains the contents of bits 5 thru 10. The relationship
-`RT = GPR(_RT)` is thus always true. Uses include making alternative
-decisions within an instruction based on whether the operand field
-is zero or non-zero.
+When destination register operands (`RT, RS`) are prefixed by a single
+underscore (`_RT, _RS`) the variable also contains the contents of the
+instruction field.
+This avoids confusion in pseudocode when a destination register is
+assigned (`RT <- x`) but earlier it was the operand bits that were
+checked (`if RT = 0`)
----------------