Previously i asked a question about th relevancy of Aaker's Brand Portfolio Strategy; this is Aaker's proposition about the roles different brands can assume when a brand portfolio is used strategically.

Slightly different than this, although related to it, is Aaker's proposal of possible descriptions for brand relations among a portfolio. Aaker identifies 4 great types of portfolio, assuming the hybrid natures os many companies' portfolios that use more than one formula to manage and expand their brands.

What i wanted to know is if this way to classify portfolios is still relevant, accepted, and is there any other proposition or valid update to this scheme.

Thank you,

Paulo L