In the past, a mail file that completed the merge process might have just been sent right to the printer, assumed to be 99.9 percent accurate and deliverable. But the brutal fact is most merge processes are only capable of outputting mail files that are 96 percent accurate, meaning 4 percent of mailings will not reach the intended recipients. Moreover, maximum postal discounts will not be realized on the entire mailing.
Fortunately, a new capability has emerged that inserts a step in between the merge output and the printer that greatly improves the response rate while lowering overall campaign postage expense. This capability is extremely effective, but many marketers don’t even know of the concept. It's called campaign postal optimization.
Here’s how it works: After the merge process, the mail file is run through an advanced change-of-address and address enhancement process to ensure address information is correct and complete, improving all the missed movers and imperfect addresses not enhanced in the merge process. A final presort process is applied to the perfected address data, which yields further postal automation discounts. This extra step helps ensure that up to 99.9 percent of your mail file is deliverable to the intended recipient. In most cases, the additional postage expense savings pays for the processing.
Read the full article at: Smaller postal costs with change-of-address, advanced record enhancement and extra presort processes : Target Marketing.