Not sure if this is the right place to point this, but maybe I found some inconsistencies in your book and I thought worth it to let you know; if it's better to write about this somewhere else please let me know and I'll comply.
1) On page 145 you write:
When none of the four above exists in a non-toitoi hand without quads, a hand is always 40 minipoints if closed and always 30 minipoints if open
and on page 146:
With these hands, we can simply check if it is a closed hand or not to determine if each hand has 40 minipoints (closed) or 30 minipoints (open)
About this you give 22278m23466789s as example; but that hand if won by tsumo is 30 minipoints despite being closed, isn't it? This would be also coherent with the table on page 144.
2) Page 177:
wait is said to be good if there are at least two kinds and more than four tiles left to win on
Page 192:
wait is good if it is at least as good as stretched single or semi side wait (2 kinds–6 tiles)
While the first quote seems to include five tiles as good waits ("more than four tiles"), the second exclude it ("6 tiles"), so the case of five tiles seems unclear.
Not sure if this is the right place to point this, but maybe I found some inconsistencies in your book and I thought worth it to let you know; if it's better to write about this somewhere else please let me know and I'll comply.
1) On page 145 you write:
and on page 146:
About this you give 22278m23466789s as example; but that hand if won by tsumo is 30 minipoints despite being closed, isn't it? This would be also coherent with the table on page 144.
2) Page 177:
Page 192:
While the first quote seems to include five tiles as good waits ("more than four tiles"), the second exclude it ("6 tiles"), so the case of five tiles seems unclear.