Daf Yomi - Yoma 71 - Kesones was Shatnez?

It is stated in the Mishna that the kohen gadol wears eight begodim and the kohen hedyot dons four. The Yerushalmi comments that each one of the kohen's clothing served as an atonement for a specific aveira. The shirt is a forgiveness for the transgression of wearing shatnez (wool and linen together). The commentators on Midrash explain the connection between the shirt and shatnez because the shirt itself was shatnez. This is extremely bewildering for it is explicit that the shirt of the kohen was made solely from linen and there was no wool in it?

There is a famous answer given based on a riling of the Rama. He rules that one is forbidden to wear shoes of linen and socks from wool, even though they are two different articles. The reason for this is because it is considered like one since the socks cannot be removed without first taking off the shoes. The same can be said regarding the kohen's shirt. The kohen gadol wore the robe on top of the shirt and the robe was made from wool. Since the shirt could not be removed without first taking off the robe, this can be considered shatnez.

There are those that say that this can be the reason why the kohen gadol puts the headplate (tzitz) on last. In truth, he can lift his hands in the air and wiggle out of the shirt without removing the robe. However, there is a halacha that he cannot lift his hands higher than the tzitz because it has Hashem's name inscribed on it. It comes out that the wearing of the tzitz is what creates the shatnez of the shirt and the robe, hence we delay the placing of the tzitz until the end.