Well, he seems to get inventive both with grammar
故常無欲,以觀其妙;常有欲,以觀其徼。which he translates as "Consistently desire Without-form In order to study its mysteries. Consistently desire Has-form In order to study in frontiers" -- here I'd probably object to the syntax interpretation, since the predicate should go before the object, as it is in english: 故[therefore] 常[permanent, always, normal] 無[have not] 欲[desire, want],以[thus, thereby] 觀[see in detail,] 其[its, his, hers] 妙[mysterious, subtle, exquisite];常[permanent, always, normal] 有[be, have]欲[desire, want],以[thus, thereby] 觀[see in detail] 其[its, his, hers] 徼[border, limit]。 Therefore I'd suggest a translation like: Therefore, always having no desires [one] thereby observes (comprehends) one’s subtleness (hidden perfection). Always having desires [one] thereby [merely] observes one’s [outer] limits."