Pang Tong presents the chain-link strategy

In Romance of the Three Kingdoms, Pang Tong plays an important role in The Battle of Chibi. He pretended to have defected to Cao Cao's side and presented him with the chain-link strategy. Cao Cao's men weren't used to travel by water and became seasick. The ships were linked to each other to make them more stable and prevent them from getting seasick. However, the real reason why Pang Tong presented this strategy was because Zhou Yu and Zhuge Liang were planning to use fire against Cao Cao's fleet and with the chains being linked together, the fires would surely spread across all ships.

What happened historically?

 * Historically, Pang Tong did not participate in the Battle of Chibi.
 * Historically, it was Cao Cao's idea to link the ships.