Having external file drawings as separate entities inside Creo philosophy is very useful, specially when dealing with large and complex parts and assemblies, where there is a need to eventually share work among several team members, besides allowing operning only the 2D drawing files, when someone will not look into the 3d geometry.
Having said that, there are CAD packages, namely VX, if my memory seves me well, that did allow each part or assembly to have embedded 2D drawings. For small parts and assemblies, or with simple 2D drawings, where the drawings are made by the same user, and there is no need to share work, there are also advantages to have the option of creating an inside part or assembly embedded drawing.
In our case, when trying to implement automation, designing "skeleton" start parts for later deriving 3D geometry to finalize the parts, using a multibody approach, where each body will define the size and positioning of later derived parts, it would be extremely usefull to be able to create inside the part, multiple embedded drawings, where each drawing would 2D detail each "Body" (as a future part), or to 2D detail the whole part, as a conceptual assembly. Since we can use "Save a Copy as" to save the 3D part with a different filename, and edit the bodies dimensions as another "conceptual assembly", it would be a lot easier to manage the associated simple 2D drawings if they were saved inside the part, instead of having to manage that association as external drawing files.
Currently (Creo 7), it's also not easy to detail individual bodies, unless we use layers to hide all the bodies except one. Even with external drawing files, the 2D environment should allow us to select each body (or group of bodies) to be associated with a general view, and it's associated projected views. Solidworks allows that easy selection of the body to be used to detail in 2D.
