How Are 13 Chulyot with 7-8-11-13 Accomplished

In the Radzyner method, it seemes as if a chulya is made by the looping of the shamash around the wraps included in that particular chulya, yet he seems to maintain that all 13 chulyot are composed of 3 wraps, while he loops around only 9 sets of 3, and other sets of 1 and 2. I understand that this is needed in order to keep the minhag of the 7-8-11-13, but how then does he say that the strings are divided into 13 chulyot of three? Does he? I know that 9 falls between 7 and 13 so it is okay, but it at least seems to me from your words (correct me if I am mistaked) if not from his own words that you do divide 13 sets of 3. If so, how is this accomplished?

Yes, the Radzyner method tries to maintain the 7-8-11-13 while at the same time implementing the 13 chulyot of 3 – since this is physically impossible (due the double knots breaking up the 7-8-11-13), he compromises and configures the chulyot around the double knots to keep the tree wraps of a single chulya.
– Mois Navon