Hittite 'hartagga' (was: HORSA vs. EXWA)

--- In cybalist@yahoogroups.com, "Tavi" <oalexandre@...> wrote:

> I'm afraid there's no such "thorny cluster" here. As I've explained in
> another post, the geminate velar of Hittite hartagga- must be a suffix
> like the one found in the Turkic cognate qarsaq 'steppe fox'. With the
> help of external data, I reconstruct an affricate sibilant (possibly
> alveolo-palatal) in the internal cluster *rC.

What's the evidence for a 'geminate velar' in 'hartagga-'? While I haven't located the spellings of the word, 'hartagga-' seems to be a reading of a spelling of /hartka-/.

Richard.