I'm guessing the same thing now that I have time to think about it, since otherwise the additional Mat loss -15% part of the enchantment would be 100% useless.
Also, some quick guesses w/ GTrans says that it is indeed capped @70. "(70上限)" = "(70 upper limit)", and I'm pretty sure those are the kanji used.
.... Just realized something rather odd. There was no mention at all about the new synthesized equipment mentioned in the notes. Normally, they like to include anything new to pad out the broadcast.
YouTube bugged out a bit while I was watching. I don't think the actual "like" numbers were quite this high: