Possible pvp talent macro bug

Continuing the discussion from Nectrotic Strike Macro help (PVP Talent):

I think I have uncovered an issue with macroing pvp talent abilities in the way you can macro normal talent abilities. the normal 7 rows of talents you can use something like the following example:

#showtooltip
/cast [talent:5/2] Diffuse Magic; [talent:5/3] Dampen Harm

The intended goal is to keep a single keybind and have the ability switch based on what talent you choose. For some reason I have not been able to reproduce this functionality when referencing the pvp talent row. Is this intended or something overlooked?