While using source control I recently encountered one aspect of traditional Domino development that does not play well with DXL round-tripping. Because I tend to be merging changes outside of Domino Designer, in my preferences (Domino Designer > Source Control) I have Use Binary DXL for source control operations deselected.
CSS stylesheet inserted in the HTML Head using Create > Resource > Insert Resource appear as rawdata elements, so are fine.
Once aware of it, it’s not a huge problem to change. Simple HTML can be used in the HTMLHead to insert the same script library. But it is something that should be borne in mind when using source control with existing Domino web applications.