I'm sorry if it sounded that way, but I wasn't being condescending.

Well, ah, certainly no hard feelings (I'm just not like that), but
'remedial' does have a negative connotion to many, though it's true that
there's really nothing so about the dictionary definition of the word.

Airport operations and following taxi instructions are basic knowledge
required to fly safely. You might think it's safe to hold short of a
runway "just in case," but you could have caused a taxiway incursion
by stopping suddenly.

Well, yes, it's most certainly true that the sudden stop was not the
best way to have handled the situation! That said, I'd hope nobody is
on my tail so closely that that's going to cause a collision hazard.

The specific scenario I raised is, unfortunately, apparantly an area of
unclarity for a good number of active pilots. I fly out of D and C
airports quite regularly, and, for one thing, any other time this
situation has arisen I had in fact been explicitly told by the
controller to cross runway x when runway x was active. Seems that most
or many of them like to keep these things crystal clear despite what the
regs say. I cannot recall a single other time when I was given a taxi
instruction that implied crossing an active (but not the destination)
runway without a specific instruction to do so. This may happen at a
good many airports regularly, but I don't think it's the norm at some at
least.

that tower controller (it's possible you misunderstood each other while
discussing this). If he doesn't know it correctly, bring him along to
someone who does, or at least show him the book.

I didn't talk to him, the CFI I mentioned did, and I'm certain that said
CFI had complete understanding of what had occurred.