There are 3 hard to discover features in P&ID that I particularly like and wanted to make some noise about. (yes, yes, I know you shouldn't end a sentence with a preposition. )
1. CLASSIFY. If you either type classify at the command line or select classify from the right click menu, you can select AutoCAD objects and make a P&ID item. So if you have an existing block or linework that you want to make into, say, a Horizontal Centrifugal Pump, the classify command will allow you to do just that. Whatever you pick will become one P&ID item.
2. ANNOTATE from the DATAMANAGER: Any text on the Data Manager ESW grid can be dragged from the grid onto the face of the drawing. When you drop the text on the drawing area, you will get a stretchy drag line that points you to the parent component. You can then click to place the text on the page where you want it. Text gets the current AutoCAD Text Style.
3. IMPORT LOG: After you've exported the data to excel from Data Manager, made changes, and re-imported the data, your accepted and rejected choices are recorded in text files called ACCEPTED_date.log and REJECTED_date.log. These files are found in your MY DOCUMENTS directory.
Just a few things you might want to play around with on a cold winter night. Happy Solstice.