Make it easier to understand Section 4.1 (Recursive Resolver behavior)

[Philip-NLnetLabs]

From Michael Richardson:

>> Could this document in section 4.1, paragraph two, give names to the two
>> parallel queries? I don't care what name you use, Abbott and Castello if

you l
>> ike, but give
>> them names?

> Just checking, you want names for the legacy delegation query and for the
> IDELEG query?

You listed pairs of queries above.
One was for NS (Abbot) and one for IDELEG (Castello).
I'm asking you to name those two queries. I don't care what.
Then we can talk about a qname-minimized Abbot query.