> Are the following valid:
>
>                 incf    INDF,F          ;Increment register pointed to
> by INDF and save in register
>                                         ;pointed to by INDF

Should be fine, though some assemblers prefer IND.

>                 subwf   INDF,F          ;Subtract W from register
> pointed to by INDF and place
>                                         ;result in register pointed to
> by INDF

Ditto.