That's true. When it was simply the we'll text you when the room is ready I was about 50/50 on whether or not I actually got the text. I've also done online check exclusively since that started and it did make the line go much faster.
But I've gotten the email to bypass the desk every single trip since that feature started and that has been nearly 100%. I had one trip...the last trip actually, where I had to ask to change rooms due to an allergic reaction. Other than that I have had no glitches.
Although now I've probably jinxed myself