No...in Photoshop you had to create a whole file which when using the Duplicate does add a "copy" in the file name. Lightroom's Before/after is a completely different function. It uses history to show the image Before and the current state in After. Before/After has been in LR for a while. Also, when making any adjustments when soft proofing, LR give you the opportunity to create a new Virtual Copy and will add the proofed profile name in the VC name. Really, pretty slick...