I really would like to assign a caption to multiple pictures at once without using the metadata template.
I already use the local template from Ingest menu for some overall general metadata and the global one during upload/saving for some general metadata depending on the export target (agency / customer /...). So fiddling with the templates leads to a back and forth between the different templates especially if I'm on location and want to deliver fast.
In other tools you could just select multiple images(, activate auto-sync or sth. like that,) and enter the caption for those selected images the same way as you would do it for a single image.
Just to make it clear: This should not lead to a full sync, but only sync the edited field. So if I change the description of one image, while auto-sync is enabled and several images are selected, all selected images should get the entered description, but keywords, headline or other fields should not be synced then.