1/ Of all the weird stuff I have ever seen Win32k.sys do, and trust me, I've seen a lot, I have to say this takes the icing on the cake. This is now all over it. Is there a new dev team that does't understand how (why?) the code base works? Is someone desperately hunting a bug?

2/ I am a huge fan of assertions -- use them all over the place. But runtime assertions, with textual strings which send a live crash/telemetry back to the developer? They also happens to basically provide a guided map to where the bugs are. I love seeing words like "should". 3/ Well, I guess this is what happens when you no longer really ever build/use checked builds (apart from some teams) which had ASSERT_MSG providing similar behavior, and don't make them avaialble for customers anymore. Now you have them in retail builds causing live dumps. 4/ So, if anyone still cares about Win32k.sys (I don't) -- there's now a map of 'things you should try to contradict/make true/code paths you should reach'. Have fun.