It is very straightforward.  Specifically, i) Create an OB model of the firm’s income statement from last year, ii) relax its assumption of a fixed forecast and iii) the results will demonstrate how much profit the firm forfeited by not sizing and allocating last year’s marketing expenditures for the best possible profit.

To illustrate the business case, a simple proof of concept OB model was created for the previous year’s income statement of an iconic global gift company. The results were astonishing: the firm had left 50-150% of last year’s profit on the table.  See the article, The OB Really Works for the details.

It should be noted these results were as good as they were because the firm had significantly under invested in new markets and over invested in new markets, the results will always necessarily be better because mathematically:

Opt (COGS + SG&A) will always be better than Opt (COGS + G&A) and Opt(S)