Do I need to have the 'Objective' or 'Headline' section for my Résumé / CV?

The mechanics of reading an English document flows from left to right and then in the downward direction. And since a recruiter would probably spend only around 10 seconds to skim through your Résumé / CV, the top section of the document is the most precious 'real estate'. Logically you would want the essence of your resume to be there to inform the recruiter how well you and your skills (like a product's feature) would be able to fulfil the requirements of the company (like a product's benefits) and answer to its needs. Remember that if a company advertises for a position, it is looking for someone who can specifically help it solve a certain problem / or a range of problems and a candidate needs to be clear if he/she is qualified and possesses the ability to provide the solution.

For every one position, there may be many potential candidates who can do the job but how is the recruiter to know exactly "who" to call for an interview? A nicely written brand statement / objective helps the recruiter get a clearer impression of you and your ability and sustains interest in reading your whole Résumé. Many candidates have impressive achievements and career records but those strengths were not always highlighted to their advantage. So if I were to answer to a specific job advertisement, then a brand statement or headline would be appropriate - but if I were to "cold-call" by writing speculatively to enquire for a job opening, I would state my objective in the Résumé.