I think you just made a really good argument for leaving the camera set to sRGB. It's the smaller color space so if you don't see any clipping in the tiny, questionably precise histogram in sRGB, you damn well won't have any clipping in the image when processing the RAW file.
Nah it just means you crippled RAW even more than you had to (although if all you ever care about is final sRGB output I suppose not).
I don't see how this would cripple the RAW output. The setting only affects the preview, so at worst you take a picture, look at the sRGB based histogram and decide the exposure was good, when it might have been possible to push the exposure a little bit more.
Now look at the converse situation. You set the camera to AdobeRGB, take a picture, look at the histogram and see that it is at the very limit of the cameras dynamic range...any more exposure and you would have clipping. Now you import the RAW and when output to sRGB find that there is clipping.
Honestly, the margin we're talking about (if not imagined) must be tiny.