Hi Damian —
Both are useful, and which to use depends on what behavior you want. In the range 1..10 by 2 both low and lowBound are 1, but high would be 9 (the highest index represented by the range) and highBound would be 10 (the high bound as defined by the range). [ATO]
In a range strided by 1 or -1, both calls will always return the same value.
-Brad