How does line item-based systems impact optimization effort?

A line item-based system significantly enhances the ability to optimize campaigns. In such systems, each line item can represent a unique set of targeting, bidding, and creative instructions, which allows for a more granular and focused approach to optimization. Advertisers can adjust bids and tactics on a case-by-case basis, honing in on what works best for each specific audience segment or placement.

This level of detail provides advertisers with the opportunity to analyze performance at a more segmented level rather than relying on broader aggregates. Consequently, this results in improved efficiency and effectiveness in campaign execution, enabling marketers to react swiftly to performance data and adjust strategies as necessary.

The notion that this system requires multiple permutations for bidding does highlight the complexity involved, yet it's fundamentally about the richness of targeting and optimization potential it provides, allowing campaigns to evolve and improve continuously. Therefore, the ability to conduct optimization efforts is significantly strengthened in a line item-based setup.