While holding office as
Imperial Chancellor, Gu Yong managed the administration well. He assigned his subordinates to their respective appointments in a way which not only generally suited their preferences, but also allowed them to put their talents to good use. He also often went on inspection tours to assess local conditions and see if policy changes could be made to improve the people's lives. When he had new ideas, he secretly proposed them to Sun Quan. If his ideas were approved and implemented, he gave the credit to Sun Quan instead of claiming it for himself. If his ideas were rejected, he kept quiet and did not reveal anything. As a result, Sun Quan trusted and regarded him highly.
A reticent person Although Gu Yong always maintained a polite and respectful tone when he spoke up on issues in the imperial court, he was also known for standing by his principles and holding his ground when he had to. On one occasion, when Sun Quan sought feedback from his subjects on policy matters,
Zhang Zhao used the opportunity to ask for a review of the laws. He presented the findings he collected over a period of time, and pointed out that the laws were too strict and the penalties for crimes were too harsh. Sun Quan did not respond to Zhang Zhao and instead turned to Gu Yong and asked him: "Sir, what do you think?" Gu Yong replied: "My observations coincide with what Zhang Zhao just described." Sun Quan thus approved Zhang Zhao's request for a review of the laws. Sun Quan often sent his palace secretaries to consult Gu Yong on policy matters. If Gu Yong approved, he had food and drinks prepared for the secretaries while they discussed and refined their ideas with him. If he disapproved, he appeared solemn and remained silent, and had no food and drinks prepared for them. The secretaries then scrapped their ideas and went back. Sun Quan once said: "If Lord Gu is happy, that means he approves your idea. If he doesn't say anything, that means he thinks your idea can be improved. When that happens, I will think through again carefully." This quote showed that Sun Quan had much faith and respect for Gu Yong.
Response to suggestions to launch border raids Around the time, many Wu military officers in charge of defending the border along the southern banks of the
Yangtze River wanted to gain credit for making contributions in battle, so they often wrote to the imperial court to suggest launching small raids on Wu's rival state
Wei in the north. When Sun Quan sought Gu Yong's opinion on this, the latter said: "I heard that in warfare, one should refrain from trying to make petty gains. When these officers make such suggestions, they actually just want to claim some credit and glory for themselves, rather than for the greater benefit of our State. Your Majesty should ban them from making such suggestions. If a suggestion doesn't do much harm to the enemy and isn't sufficient for us to showcase our military prowess, then it shouldn't be taken into consideration." Sun Quan heeded his advice. Throughout his tenure as Imperial Chancellor, Gu Yong never shared his opinions on policy issues except when he spoke to Sun Quan in person.
Lü Yi scandal Around the 230s, Sun Quan appointed
Lü Yi, whom he highly trusted, as the supervisor of the bureau in charge of auditing and reviewing the work of all officials in both the central and regional governments. Along with his colleague Qin Bo (), Lü Yi freely abused his powers by picking on trivialities and falsely accusing numerous officials of committing serious offences. As a result, some officials were wrongfully arrested, imprisoned and tortured during interrogation. Gu Yong was one of Lü Yi's targets. The latter initially prepared to make a case against him for incompetence and ask Sun Quan to remove him from office. However, after an official Xie Gong () pointed out that
Pan Jun, the Minister of Ceremonies, would most likely become the next Imperial Chancellor if Gu Yong were to be removed from office, Lü Yi immediately dropped the case against Gu Yong because he knew that Pan Jun resented him and would take action against him if he became Imperial Chancellor. Lü Yi's abuses of power finally came to an end in 238 when Sun Quan learnt the truth about him and understood the gravity of the situation. After removing Lü Yi from office, Sun Quan had him imprisoned under the watch of the Ministry of Justice, and then ordered Gu Yong to conduct an investigation. While interrogating Lü Yi, Gu Yong maintained his composure and performed his job professionally. Before Lü Yi was escorted out, Gu Yong asked him, "Do you have anything else to say?" Lü Yi
kowtowed and remained silent. When another official Huai Xu () started scolding Lü Yi, Gu Yong sternly rebuked Huai Xu: "As government officials, we should follow the laws. Why must you do this?" The
Eastern Jin dynasty historian Xu Zhong () disapproved of Gu Yong's handling of Lü Yi's case. He pointed out that Lü Yi's actions had severely damaged the integrity of the Eastern Wu government and reduced people's trust in the government. Xu Zhong argued that Gu Yong should not even provide Lü Yi an opportunity to defend himself, because if Lü Yi pleaded not guilty and Gu Yong submitted his plea to Sun Quan, there was a risk that Sun Quan might believe that Lü Yi was innocent and therefore release him. If that happened, then, in Xu Zhong's opinion, the efforts of
Sun Deng,
Pan Jun,
Lu Xun and the others who stood up to Lü Yi's abuses of power would have been in vain. Xu Zhong also argued that Gu Yong should not reprimand Huai Xu for scolding Lü Yi because Lü Yi deserved it for his evil deeds. ==Lecturing his grandson on proper behaviour==