Is it the details necessary to *construct* rotes and suchlike?
Yes, exactly those details. For a couple of reasons. Without a summary, you have to hunt down the rules in the rules section. That's not very handy for players without the rulebook (And in my experience, usually there is only one book to go around at the table. Fact of live if the majority of your gamers are casual ones). Also, it would be nice for the GM to have an at a glance summary for use with his NPCs. There is no "at a glance" summary for constructing rotes and thaumaturgy spells in the whole book. Charts in the appendix would remedy that.
My players will not be relying on rotes very much, because they are used to Mage and thinking about potential spell effects on the flight.
The intent was for 411 to cover 90% of what you'd need in-conflict, in-play, at least.
Well, I'd say it covers about 30%. Because the actual mechanics for casting your spell are quite easy to remember, as soon as you have determined the difficulty. And determining the difficulty relies on constructing the spells in the first place.
Since yesterday, I am speaking from experience. Because appropriate to the subject of the thread, we ran our first DFRPG scenario. It went rather well