I mean, it's like profile post comments. This is really a great idea, of course what would be an even greater idea is if it actually release. While it is true that progress is an amazing thing and liking comments would be a nice touch.
No. This has already been requested and I've already turned it down. Showcase Items can have Discussion Threads associated with them for this functionality. The comments system is designed to be a comments system, not a discussion system. You'll have to modify this on your own.