I left for a ski this morning, grabbing my poles and skis from where they live in my car. I then classic skied for almost ten minutes before noticing that my right pole was a skating pole. And even then I didn't notice that my poles were different lengths, I had looked at my hands to see how far apart they were when I double poled and thought, "that's strange, I wonder if I always bring my right hand up higher than my left." Then I figured it out and skied back home to get my other classic pole. So later today I duct taped the tips of my skate poles so I wouldn't have to feel like an utter fool again.

They say a clever man learns from his mistakes but a wise man learns from the mistakes of others. It's too late for me to be wise, but not too late for you (presumably).