When creating a "Send Keyboard Input" shortcut, if the sequence involves sending a lower case letter immediately followed by an upper case of the same letter, both letters are sent as lower case.  The same is true for the opposite scenario, where if you first send a capital letter followed by lower case of the same letter, both result in upper case.

For example, the sequence:
Sequence -- f:Shift+f
Expected result:  fF
Actual result:  ff

Sequence -- Shift+F:f
Expected result: Ff
Actual result:  FF

Work around:
to produce the string fF, use the sequence:
f:f:Backspace:Shift+F