The Video Game Critic

Extra Credits did a really interesting video on the Blue Shell from Mario Kart.  A lot of people think it's a horrible item, and that it favours bad players and is unfair to good ones.  I used to think that, but even before this video, I had made peace with the Spiny having played a lot of MK8.  Like they say here, there are ways around the Blue Shell, and slamming your brakes is a great one, as long as you know where everyone else is.  

The video shows how much design thought probably went into that shell, and how it is constantly being tweaked to make it more enjoyable for everyone.  It kind of raises my overall opinion of Nintendo's design philosophy for this franchise. As well, it shows how even things people think of as being "casual friendly" can come from great game design for everyone, not just from "dumbing down" games to remove skill.  
  

http://www.youtube.com/watch?v=LFfga8-3SZI

People complain about the items in Mario Kart way too much.

You have to remember the law of averages. Some races you have terrible luck, but it will even out. And you improve your luck through item management.  And frankly, if you are playing against highly skilled players, items will only help you win (or even finish high) once in a very great while. So to say the blue shell is game breaking or casual friendly or an equalizer is beyond laughable.

The problem with Blue Shell was put to rest when the devs allowed it to also hurt people in its path to first as well as the first player, and by allowing people in 4th to sometimes get it. Also it was practically impossible to dodge

In DS, Wii and Double Dash!!, it was pretty much useless,since it just flew over to the guy in first,but only someone in a low position could get it. This would not help the sender, and would end up just switching the random 2nd or 3rd place player into first.

Super Circuit,64, and everything after 7 were far smarter about it.