My rating increases despite using hints !

There seem to be a flaw in the rating system of the chess mentor. I usually use hints the first time I do a lesson and receive a 75% to 95 % score. My rating still increases.

But when I review the lesson a second time I oftentimes get a 98% to 100% score, and the previous failure is gone in my stats.

Is this rating boost a conscious plan from chess.com or is it just a flaw in V2 ?

It is a conscious plan from Chess.com to get you to repeat lessons. The theory is that you may learn something.

Most people know that Chess Mentor ratings don't matter. 

The failure may be gone in your stats but you don't get a rating boost.  Your rating goes up or down only the first time you do the lesson.  Still useful of course to review and try to get those %s up to 100.

Yes, at least the mentor has realistic problems rated by OTB game analysis. A mentor problem rated 1600, would in online games probably be rated 1000-1100.

I'm currently facing an 1100 rated player that's kicking my ass hard, with tactics only seen at the 1800 level in the tac trainer and the mentor.