If this is being used as a means to allow Retro to actually craft Challenging levels, whatever.  Just don't penalize me if I end up seeing the option prompt due to a tricky section of the game, and it looks like we won't be.

Fair enough. This feature seems more appropriate for this game, which looks pretty challenging from all that we have seen. I won't use it, but I wouldn't be surprised if I did lose 8 lives in a level and bring up the prompt.

It doesn't say the exact requirement for the guide appearing, so it may not be losing eight lives in a row. It will depend on how generous the game is with 1-ups, and traditionally, the Donkey Kong Country games hand out a good amount less than the Super Mario games.

That's true. Not only are lives less frequent in Donkey Kong Country, but they are harder to find on top of that. It is easy to accidentally skip over one of the K-O-N-G letters in a level and in the rare event that you see a DK balloon, you have to be very quick or it will just float away.

DKCR is pretty generous with lives, especially since you can buy them for cheap at Cranky's shop.

I'm fine with a generous amount of lives.  I'd much rather be given copious extra turns than have the actual level design dumbed down or simplified.  Sure, there's a tension that comes with having just one more life, and if you lose, it's all over...  but I'd much rather have 99 lives (like in NSMBWii) and be able to mess around and try for crazy stunts and impossible feats without worrying about having to start over.  BIT.TRIP RUNNER has infinite lives, and it doesn't make the core experience any less fun (or insanely difficult).

The Super Guide is what a think a way for non-gamers not to be discouraged if they keep losing all the time. Nintendo crafted something wonderful with the Super Guide in NSMBWii, since, if you think about it, if you're a first time gamer experiencing a Mario game for the first time, and you don't know what the hell you're doing, the Super Guide is there to ease your frustration...hopefully.