Have I mentioned that Beorn hates baths?

Allow me to explain the sequence of events that happened to me today.

1) Beorn and I decided we were going to the dog park (well, I decided we were going to the dog park).
2) We get to the dog park. We go to this particular dog park because the one closest to our house has two massive mud puddles that Beorn loooooves to jump in, and this one does not. Also, it is adjacent to a biergarten, so win-win.
3) Someone coming out of the dog park says, "Hey, look out for the mud puddle!"
4) I take this advice and when we enter the dog park, do look for aforementioned mud puddle. I do not see it.
5) Beorn does.
6) Beorn runs to the mud puddle.
7) Beorn sits in the mud puddle.
8) Beorn lies down in the mud puddle.
9) Beorn rolls over. In the mud puddle.
10) Several times.
11) All while ignoring me.
12) I give up and resign myself to the fact that my dog is now completely covered in mud. COMPLETELY. There is mud in his ears. He hates baths, but now... he must have one.
13) Some helpful fellow dog-parkers inform me that hark! There is a pond over yonder!
14) We go to the pond across the street. Beorn immediately jumps in the water and begins swimming.
15) I rejoice!
16) I also enter the water and pour a approximately one tablespoon of water on Beorn's back, which, as we have learned, is receiving a mud-skin-treatment.
17) Beorn FREAKS THE EFF OUT ABOUT THAT TABLESPOON OF WATER ON HIS BACK AND OH HELLS NO HE'S HAVING NONE OF THAT ACTION.
18) Beorn sprints up the bank. I am holding the leash and fall in the mud (this seems to be a theme with Beorn and I lately). I try to pour more water on Beorn's back. He runs under a bench, which I run into, cutting my leg. Beorn is shaking and crying. I am trying not to laugh and comfort my dog. I give him a treat. Beorn tries to "shake" with me using both paws and scratches my arms.
19) I decide we are done with the "bath" in the pond.
20) We go to the biergarten. I get myself a lager, and take a photo of the aftermath of this ordeal. We are both tired.

There's probably a lesson here somewhere, but I couldn't tell you what it is.