In the case of your first question, it's because it gets boring if I simply repeat the same language over and over, so I tend to vary it a bit, and sometimes the slightly different phrasings will help unlock a key idea for certain students
In this chapter I make a big deal about how the error of causality is when it occurs in the conclusion, so when I say on page 267 that they lead to causal conclusions, that's the same as saying leads to causal errors.
The Advanced scenarios are advanced because the language they use lessens the force or introduces extra elements. In those instances, you again have to be a tracker: you have to watch for language that introduces these ideas. However, English has so many possible wordings that there are times when it isn't feasible to produce a basic list of indicators, because there are just too many to make it useful! And, as with our discussion about Weakening questions, you aren't applying anything here—you are recognizing when these situations occur (and Advanced causality occurs less frequently than Basic causality, so get Basic locked down first!). You can't apply something like a partial cause, you have to watch for statements that indicate that the cause under discussions is just one of several things that contribute to the effect.