It was just a flight of stairs - or so it seemed. It looked just like any other regular staircase, with people occasionally walking up or down, just going about their business without ever really noticing the stairs.

That's probably the very reason why it became the perfect place to create a bubble in.
You'd make a stop once or twice where nobody ever does, whether or not there was an audience, and you'd have managed to freeze a few seconds in time - litterally freeze 'em because afterwards nobody could pick out exactly what had happened and what was different, nobody but you and, I guess, potentially me. You had found the perfect mix of subtle and obvious.

And I'm sorry I let that flight of stairs get to me at all - I want to apologize for letting the staircase catch me.

But to me, that's all it ever was - a regular flight of stairs.