I hope you weren't the guy on the singlespeed I rudely drafted off of and then passed up on an ascent on the way home from work yesterday. I did ask permission to draft then offered to pull, but took the lead too quickly and dropped whomever it was sort of by accident. Gotta pay better attention to the rear when taking the lead on an ascent. My excuse is that I was in a rush as my son was on his way to the doctor (he's fine). Another reason I did that was the rider looked strong and I didn't want to hold up the show.
If that was you, sorry. If not, sorry to whoever you are.
Good question in the OP.