Is this about to get quite nitpicky? Yes. Is it worth it? Only maybe . Does it belong in proofreading? Also only maybe.

On the examples TN list on p. 13, one of the examples for TN 7 is "A heroic task such as outwrestling a troll or naming all your ancestors in order ." (Emphasis added)

I don't think naming ancestors is the best use of an example for TN 7, for two reasons:

1. I bet there's probably a heroic task that's common to more gaming groups. Like composing a haiku that move's the emperor's heart, inspiring a new course of action (ok, maybe that one in particular is TN 8 Legendary)
2. From what I know of memory, it's not particularly accurate. You either know that list or you don't, because it's implicit memory (like muscle memory, e.g. singing your favorite song from age 14), not explicit memory (like knowing that the Doji are a Crane family).

Yes it's an extremely long list. Yes learning it would be difficult. But recalling it wouldn't be (if you learned it well).

Committing your ancestral lineage to memory after studying your family tree for one evening would probably work for TN 7, though.

This is a nod to older editions of L5R, where this exact same example was used to showcase heroic TNs. I'm pretty sure it was a case for 3rd and 4th editions

It bugged me in 4th, too. Definitely not a high level concern.