I did try to find more information on the case that butterfly dreams mentioned, but my google search was a bust. I did find one mention on a blog of someone commenting that they saw someone collapse of a heart attack right after drinking cold water and the paramedics said it could have been a contributing cause, but no other info that really helped put this in context.
Certainly everyone do what you want. It probably won't hurt not to drink icy water after exercising. And maybe it will help. I just think this kind of scary information provided without a lot of context can end up doing more harm than good. Maybe someone will decide, after a workout not to drink water because it's too cold and then have issues as a result of not hydrating properly.
I often hear people on this site say that they no longer listen to research evidence because it all contradicts eath other so why bother. But then we will listen to scary anecdotes and think nothing of it. Maybe it's the researcher in me, but I try to understand where evidence and information comes from. Sometimes the research evidence is contradictory yes, but not so much if you start to understand how the research process works and how it is often mis-reported by the media...
The problem is that anecdotes and stories are less reliable, but because they are so vivid we listen and make our decisions based on them. (and there is a lot of research in psychology that makes this point).
Anyway, I'll get off my soapbox now. I don't mean to offend any one. It's just that I try to teach my students not to simply rely on anecdotes/stories when they make decisions because of their unreliability.
One final disclaimer: I am not a medical doctor and certainly don't want it to sound like I am dispensing any kind of medical advice at all!