All you need to know about Carpenter's Square - 12
As will be shown, the missing stone at the hoshi point is a major defect for black.
wants to use the same attach tesuji. White can simply play and , a combination that would not work in the standard Carpenter's square. But because of the defect at , black's eyespace is reduced and after the corner is dead in Bulky Five.
is also possible. attempts to reuse the standard solution in Diagram 2.2. However, is good and black cannot survive.
If black plays , white again can exploit the weakness at to reduce the eyespace. This corner is dead too.
is also possible. Shown here is a different way to form Bulky Five.
Conclusion: this corner is very weak with the missing stone at hoshi point. There are a number of other ways to kill this corner. I will leave the readers to practice and find them all.