I think performances are fair game for critique, so long as the critique is constructive. By constructive, I mean that if you are going to tell someone they shouldn't do A, perhaps you can recommend they try B. If I record something that sounds objectively bad, I want y'all to tell me about it. But try to be more specific than "you suck".
Any time you record someone else's work, you are going to invite comparison to the original. Kdub tackled a difficult tune, and that should be acknowledged. The recording, like all recordings, has shortcomings. Kdub wants to hear about them, but also needs to hear what he got right.
Edzbug62 didn't blow it because he was critical of kdub's performance - several of us were critical of Kdub's vocal performance. Edzbug62 blew it because starts out by saying he listened to 10 seconds of the song, declared that the song was unfit for him because he is a perfectionist, and then tried to make a joke of it. All in all, Edzbug62 spent way more time creating his unhelpful post than he did listening to Kdub's song.
And with that, I hope Kdub's song returns to the spotlight here.