I find dry peat becomes full saturated overnight really.I agree. This is a very helpful guide.
So what do you think can get waterlogged more easily, peat or sphagnum moss? You only mention waterlogging with sphagnum.
The reason I ask is because I could not find perlite anywhere within the last couple of weeks and I had to go on ahead with my repotting. I had to choose between using either pure peat or pure sphagnum without perlite or any other aggregate as my growing medium. ...I went with using only pure peat.
Either moss or peat is fine. I know someone with a fine collection all potted in 100% peat.