Adding captions to multiple photos without erasing old captions

In older versions of Photos and iPhotos, you could multiple-select photos, add captions to all of them at once, and repeat the process with any combination of photos you multiple-selected, and the captions would simply be added to any captions previously added. This was a great feature, and I used it extensively to organize and add photos to various smart albums I created. It seems this feature was taken away at some point, and in the version of Photos I'm using now, any captions I add to multiple-selected photos simply replaces any captions that were there before. Is there a work around to this? If not, then please tell the coders to FIX THIS IMMEDIATELY!