I would like to vote for parallel and sequential sub-project. Here is an example:
Project: Company Shirt
Sub-project: Decide on Design (parallel)
- send link to online catalog to the team
- ask bob for input
- ask cindy for input
- email charlie: how many shirts do we need?
Sub-project: Order shirt (sequential)
- get shirt company phone number
- call for a proposal for shirt
- get a PO
- order shirt
Project: Company Shirt
Sub-project: Decide on Design (parallel)
- send link to online catalog to the team
- ask bob for input
- ask cindy for input
- email charlie: how many shirts do we need?
Sub-project: Order shirt (sequential)
- get shirt company phone number
- call for a proposal for shirt
- get a PO
- order shirt