There's a whole blog article written by Dario Amodei, literally linked from the text "pacing the frontier" - click that and read if you need more context and understanding. The first sentence in this press release is merely stating a fact about the timeline - this is Anthropic's first release since Amodei released the referenced article.

I think it's perfectly clear. It means improvements shouldn't simply advance as fast as possible and more specifically, it's a reference to a past statement of theirs to that effect. At that level of generality it's as clear as it needs to be.

I would say the burden is on you to explain why an offhand reference to a previous press release in an executive summary is a context where it's reasonable to expect it to settle the question to the degree of detail you're demanding.

“Pacing the frontier” is similar to the role of a “pace car” in racing.

From https://en.wikipedia.org/wiki/Safety_car

> In motorsport, a safety car, or a pace car, is a car that limits the speed of competing cars or motorcycles on a racetrack in the case of a caution period, such as an obstruction on the track or bad weather.

The meaning is not clear because they can't just come out and say they want to slow or stop Chinese model releases while continuing to race ahead themselves.

Judging by your username, is English your native language? I am Polish, too, and while very proficient, I cannot claim I am naturally accustomed to each and every phrase to the point I can claim something sounds clear or not to a native speaker.