"Yes, it does. The Society teaches that it is sinful to attend the Novus Ordo Mass, or even to attend the indult because that "supports" the "evil" Novus Ordo."
Nope. Time and again I've hear Bps. Fellay, Williamson and de Malerais say the opposite. Sorry, but you're wrong.
Seems that there's some division in the Society then. I'm only going by what's on their official website, www.sspx.org:
However, regardless of the gravity of the sacrilege, the New Mass still remains a sacrilege, and it is still in itself sinful. Furthermore, it is never permitted to knowingly and willingly participate in an evil or sinful thing, even if it is only venially sinful. For the end does not justify the means. Consequently, although it is a good thing to want to assist at Mass and satisfy one’s Sunday obligation, it is never permitted to use a sinful means to do this. To assist at the New Mass, for a person who is aware of the objective sacrilege involved, is consequently at least a venial sin. It is opportunism. Consequently, it is not permissible for a traditional Catholic, who understands that the New Mass is insulting to Our Divine Savior, to assist at the New Mass, and this even if there is no danger of scandal to others or of the perversion of one’s own Faith (as in an older person, for example), and even if it is the only Mass available.
From here: http://www.sspx.org/Catholic_FAQs/catholic_faqs__traditional.htm#attendnovusordo.
The Indult Mass, therefore, is not for traditional Catholics.
From here: http://www.sspx.org/SSPX_FAQs/q10_indult.htm.