Deconstructive Criticism

To my disappointment, the title is not a witty neologism, but a long-standing (if terminally obscure) literary term. I tried hard to understand the definition, really I did, but in the end I still prefer my own:

"Deconstructive criticism is the opposite of constructive criticism"

"But surely the opposite is 'unconstructive' or even 'non-constructive'?", you might say.
No. In my mind those are terms for criticism which does nothing at all, neither helpful nor damaging:

For me, construction means putting things together, so the opposite should be "deconstruction", or taking things apart. Not destruction, you understand, which means destroying, but more the dismantling of something which has been built.

Now that we have my definitions sorted out, how does this apply to criticism? Some examples might help.

Example 1
Constructive criticism: "You have obviously worked hard on this, but I notice a few things which could be improved. Perhaps we can work on them together?"
Unconstructive criticism: "I don't like the way you've done this."
Destructive criticism: "What a mess you've made, as usual."

Deconstructive criticism: "You've spent way too much time on this, and you still haven't got it right."

Example 2
Constructive criticism: "I know how much you like that colour, but I'm not sure it's the best choice this time."

Unconstructive criticism: "I don't like that colour at all."

Destructive criticism: "You have never had any colour sense."

Deconstructive criticism: "What on earth makes you think that colour combination works?"

Example 3
Constructive criticism: "I appreciate your point of view, but I see things differently. Can we talk about it some more?"

Unconstructive criticism: "I totally disagree."

Destructive criticism: "You always get things wrong."

Deconstructive criticism: "Where on earth did you get that idea? It's completely ridiculous."

Example 4
Constructive criticism: "You have a wonderful way with words, but I think your point might be lost in the detailed explanation you provide."

Unconstructive criticism: "I have absolutely no idea what you mean."

Destructive criticism: "You always bore everyone to death."

Deconstructive criticism: "Why can't you just use simple language instead of this rubbish?"

Example 5
Constructive criticism: "You devote so much time and effort to this company/project/organisation, but perhaps it might be time to take a step back and re-assess priorities?"

Unconstructive criticism: "Nobody should spend as much time as you do on this."

Destructive criticism: "You are not nearly as useful as you seem to think you are.

Deconstructive criticism: "Most of what you've done is completely unnecessary, and the rest has to be checked and corrected anyway."

I hope you can get a sense of the demoralising effect of deconstructive criticism, which is a more personal attack on your own values and abilities, and therefore harder to ignore, than the obvious generalisations of the other two negative responses.
In other words, deconstructive criticism is nothing more than a deliberate insult, and like all insults says more about the person delivering it than the one to whom it is addressed.  Criticism is an essential component of growth and development, but only if it is constructive. Accept no substitutes!