One thing I think the document could be improved is by adding more "real situations" when explaining what a particular process, or even a parameter, does.
For example, the description of MT now reads:
"The MorphologicalTransform (MT) process is an advanced implementation of several morphological transforms. It does so by applying a function using a structuring element (a mask)."
Nice, but it doesn't give much clue as to why this can be useful, nor a single example of how it could be used in "real life situations" (i'm not even sure it describes what is MT other than what's implied in the name of the tool!). Truth be told I haven't paid much attention to describe processes, rather, in describing parameters. So there's room for improvement, that's for sure.
I'm not talking about providing a complete example describing how to use each process (that's the job of tutorials), but a brief description letting the user know "You can use MT to do X, Y and Z for example", where X, Y and Z are common - or not so common - problems people face when processing an image. I've done that sometimes, but not all the time. In any case, I don't know how much of that should go in a reference guide versus a user's manual, but for people unfamiliar with PI, this might be one of the most sought-after kind of information where this guide doesn't do a great job yet, I think.
