Passage Summary: The author argues that engineers deserve more praise because they usually turn an inventor's raw idea into a working product, even though sometimes the inventor does that work themselves.

Conclusion: Engineers also deserve credit for their contributions to inventions.

Reasoning: While inventors sometimes do the engineering themselves, usually separate engineers are required to make an invention functional and useful.

Analysis: This is a 'Role in Argument' question, so we need to see how the specific phrase fits into the overall structure. The claim that inventors sometimes act as engineers serves as a concession that acknowledges an exception to the general rule. It shows the author isn't overgeneralizing, which actually makes the subsequent point—that engineers usually do the heavy lifting—feel more balanced and credible.