This past Shabbos someone said over to me a particular sugia they were learning in Taharas and a maklokes Rishonim (an argument between Rishonim, medieval rabbis) in a particular analysis. One Rishon was basing himself partially on a Tosefta and his understanding of it. Among the the Rishonim on the other side of the maklokes were those who brought a proof from Toras Cohanim (Sifra). While we could obviously discuss and try and understand other points of this maklokes we began thinking if there is any "klal" (general statement) in regards to what's stronger (in terms of halacha -- not neccessarily practical halacha but more in the context of such a maklokes) a Tosefta or a "braisa" (I suppose that is the best thing to call it) from Toras Cohanim. Similar questions have been asked in the past in regards to what's stronger Bavli or Yerushalmi or a Tosefta or Yerushalmi.
Is there any klal in this?
(Note: It could be since Tosefta is also just a "collection" of braisos and Toras Cohanim is also braisos it may be no different. However the fact that some were include in Toras Cohanim and others included in Tosefta might show the difference.