I think this is true in Kubiak's case for sure, he is interviewing with the Lions and maybe (doubtful) others to try and put a little heat on the Texans and to show his value as appreciated by those around the league.
However, the Texans are just covering their bases to make sure everything is cosher. In reality the Texans had only two real candidates: (1) Kubiak, (2) Ferentz (and possibly Gregg Williams). Ferentz does not look that interested and they are fearful of sitting too long on Kubiak given all the interest surrounding him.
I want to hear post interview quotes. The to sides will agree in principle tonight, although this cannot be released until the Broncos are eliminated from the playoffs.