I don't shoot in the rain often. But if it's going to rain, or potentially rain, I'll choose a lens to suit.
For example, I was watching the weather radar one day and knew a storm was coming in so I went looking for a place to capture the storm before the storm front arrived. I got to that location and took a variety of images as the storm approached but my timing was off so I was caught in the storm front passing overhead.
I'd have got no images if I didn't have some confidence in the kit. The pain in the bum bit is cleaning/drying afterwards so I usually try and shoot before/after the rain, but am okay with the correct lens on (AW/WR) if that happens too.
I did choose to pause shooting when the worst of it was coming down and there didn't seem to be much to capture. All I did was turn the camera face down to protect the front of the lens.
I will shoot with a third party lens like my Zeiss's if it's a light shower or similar but if it's serious rain I'll be fitting something with weather sealing to shoot with.
Tas