I want to start off by saying I've fermented stinky beers. I've done lagers, I've done Kolsches, I know what a stinky fermentation is...
But the Irish I did a week ago smells pretty rank. Something similar to rotten eggs but more like cat farts. Yes, cat farts. The odor has subsided somewhat but I can't smell fermented beer through the airlock. Just a lighter cat fart odor.
I knew I shouldn't but I cleaned and sanitized the lid and my hands to crack open the bucket and see what the heck was up. Well, imagine my surprise when I saw several larger, clumpy (possibly slimy?) alleged yeast colonies at the top and some smaller ones dotting the surface. I've seen some bad infections and this doesn't look like any of them, so I'm a bit baffled.
Full disclosure: This yeast packet, when received was partially frozen. I let it slowly thaw so as to not shock the yeast or injure them further. The only thing noticeable about the fermentation was the odor afterward.
EDIT: Also, it proofed just fine.