How Project Assignment functionality works in NX
Solution
If you are using 'Project Assignment' as "required - Use Defaults" then at the time of new Item creation it will assign the project to both Item and Item revision.
However, if you are using some other options in 'Project Assignment' like "Optional" then in this case if you select the 'Project Assignment Object' as "Item Revision" then be defaults project will not get assigned to Item or Item revision. So, to assign the project you have to go to Assembly Navigator and assign the project. So, in this case while assigning project from Assembly navigator if you have selected 'Project Assignment Object' as "Item Revision" then project will only get assigned to Item Revision and not for Item. However, if 'Project Assignment Object' as "Item" then in this case Project will get assigned to Item and Item Revision as well.
'Project Assignment Object' is introduced with NX 12.0.1 when you assign Project from Assembly Navigator then you have the control whether to assign Project to Item revision or to the Item as well.
However, the Customer Defaults, File > Utilities > Customer Defaults > Teamcenter Integration > General > Projects "Project Assignment Object" is specifically for Project Assignment done from Assembly Navigator, not applicable to Project getting assigned through File New dialog.
If you are using 'Project Assignment' as "required - Use Defaults" then at the time of new Item creation it will assign the project to both Item and Item revision.
However, if you are using some other options in 'Project Assignment' like "Optional" then in this case if you select the 'Project Assignment Object' as "Item Revision" then be defaults project will not get assigned to Item or Item revision. So, to assign the project you have to go to Assembly Navigator and assign the project. So, in this case while assigning project from Assembly navigator if you have selected 'Project Assignment Object' as "Item Revision" then project will only get assigned to Item Revision and not for Item. However, if 'Project Assignment Object' as "Item" then in this case Project will get assigned to Item and Item Revision as well.
'Project Assignment Object' is introduced with NX12.0.1 when you assign Project from Assembly Navigator then you have the control whether to assign Project to Item revision or to the Item as well.
However, the Customer Defaults, File > Utilities > Customer Defaults > Teamcenter Integration > General > Projects "Project Assignment Object" is specifically for Project Assignment done from Assembly Navigator, not applicable to Project getting assigned through File New dialog.
Notes and References
9399983
Hardware/Software Configuration
Platform: INTL64
OS: windows
OS Version: XP64_SP2
Product: NX
Application: NXMANAGER
Version: V12.0.2
Function: PROJECT_ASSIGN
Ref: 002-8014602