FPS & Timeline/Sequence Question

Okay so I'm not a noob but I am not an expert but I do know the rules of fps and I always shoot 180 degree shutter. I have metadata so I can check to see what my cameras setting where for each clip so I am POSITIVE the clips are shot right. 60 fps 1-120 shutter speed. I also know that you are suppose to use a 24fps sequence if you want to slow footage down to 60fps footage down to 40% speed.

Now that that is out of the way my question is this. I have 60fps footage, I slowed it down on the timeline to 40%. I accidently didn't change the sequence to 24fps but the slow motion playback is smooth as hell as if I did. It's literally flawless on every clip & I have over 20 different clips. I have also exported the projects and they playback fine as well. Did Premiere Pro silently change the fact that we have to change the sequence to 24 for a 40% slow down? Does it automatically just know or am I missing something?