breakthru
|------10...-----12...-----14...-----15...-----17...-----19...-|
|-13b15--...15b17--...17b19--...18b20--...20b22--...22b24--...-|
|--------------------------------------------------------------|
|--------------------------------------------------------------|
|--------------------------------------------------------------|
|--------------------------------------------------------------|

|----------------------------151718_p17p1517v------------------------------_____17-18-20-b22v-----------------|
|-----------------18151718-------------------------------------------15171820(20)---------------22r__20p18vv--|
|------------1416----------------------------------------------141517-----------------------------------------|
|--------1517--------------------------------------------141517-----------------------------------------------|
|-15-1818----------------------------------------15131517-----------------------------------------------------|
|-------------------------------------------------------------------------------------------------------------|

|-----------------------------------------------|
|-22r__20p18--20b22--20b22--20b22--20b22--20vv..|
|-----------------------------------------------|
|-----------------------------------------------|
|-----------------------------------------------|
|-----------------------------------------------|