This is in fact possible, as I recently discovered, much to my regret.

I discuss this topic in my latest video on my Youtube Channel.

On my recent trip to the UK and the 4NCL league I played two games where I was feeling good, my head was working well, my calculations were clear and yet in both games I blundered horribly.

In the video I try to explain why that happened.

I would also be curious to know if anything of the sort has happened to you, so feel welcome to share your thoughts.