There's already a chinochimochi tag without the space, and I haven't seen any direct evidence that it should be separated into two words (ちのちもち is what you get if you press the keys "akama" (the first 5 letters of Akamatsu, the surname of his oldest pen name) with the kana keyboard layout, which suggests to me that it should, if anything, be one word). There's also a "yaegashi nan" tag, but it's mistakenly categorized as group rather than artist (someone here confused his pen name with his circle's name). Someone with the power to alias/slave/reclassify tags really needs to sort that out.
Edit: Found a tweet by his Yaegashi Nan's (former?) co-worker which referred to him as "Chino-san", so we might be both wrong. See my post in the "Tag grouping and namespacing" forum thread.