why do you need to be so combative? I like to learn from others mistakes if I can. If you don't want anyone to learn anything from your issue, and force everyone to figure out everything for themself, thats your choice.
They've made it clear - they don't want to denigrate a library they're using, likely for free. Imagine the author of that library seeing such a comment. I'm sure you'd find it educational, but it's a terrible experience for the author.
In which case I'd recommend jerf's post at http://www.jerf.org/iri/post/2955, or my comments at https://news.ycombinator.com/item?id=30804253, or even just reasoning a bit from first principles about how intermediate slices would perform given Go's memory/execution model.