No genuine ambiguity here, it's the book (and I suspect that's typical). Even if you increased the ratio of theoretically ambiguous sentences, if that comes at

No genuine ambiguity here, it's the book (and I suspect that's typical). Even if you increased the ratio of theoretically ambiguous sentences, if that comes at a decrease of actual, practical ambiguity (uintended and unnoticed by the speaker) that's a win.