Some clarifications.
Pawq, not sure about many people having sl before it was released by smibu. I know about 7 russians (including me) who had it, and it was detectable, and only like 2 of them actually played the game. Tell about more ppl kthx. But of course hourglass was out and tasvideos is a big site, so spreading was inevitable, but this is not the point.
Bjenn, hourglass is detectable with standard configuration, but you can easily change some values to make it undetectable. It loses ability to go in slowmo and you can't easily fix old runs (they go out of sync). Knowing the reason why it is detectable in the first place makes it obvious on how to remedy the problem, but i'm not telling :p
one could have alerted the right people that could change the rules and much less people would have had it in that gray area
Imo the blatant in-your-face way worked better and quicker, even though Smibu presented it in a silly fashion. Simple alerting doesnt sound intimidating enough. For example, making hourglass sync-stable AND undetectable requires only few additional lines of code (it's open-source), so that everyone with some knowledge of C is now theoretically able to record pseudohoyl sessions offline and then replay them online without anyone noticing anything. But who cares about such improbable threat?
Little fun fact - i remember having told mila years ago about a cheated wr in an internals table and he just didn't care about it. That wr is still not removed btw, because it was made by an apparently undetectable tool (or maybe it is detectable, but no one researched it seems) by someone who isn't playing anymore. So yeah, nothing can be proven, and sadly i'm one of 2 people who were personally told by the wr maker about it, and it's not enough of a proof.