Okay, this is less a blog post and more of a question. I found some cracks-slits in my tire that I'm worried about. The first had a tiny stone embedded, but it came out easily enough, the other was a bigger slit I found close by. Both are in the thick part of the tread. I'm just wondering, is it normal for bike tires to get little slits like this? Is it safe? I dunno if they're just surface nicks and nothing to worry about, or is the tire going to disintegrate as I roll merrily down the road??