arXiv version v2 still contains some minor typos, e.g.:

p.6

e_{n,t} definition: j advances in steps of 2 within given range

B_{n,t} definition: quotient by  B_n e_{n,t-1} B_n
  (cf. B_{n,t} e_{n,t})




Published version notes:

For the example in Fig.16(a) note that the removable box 
that we have in mind to remove is the [4] (as we should have 
stated explicitly, since there is more than one possibility, but 
did not!).
The resultant balanced subpartition is not maximal in this case.