Bloomberg reports that a survey by ad effectiveness specialist Ace Metrix Inc showed that Apple’s new ‘mission statement‘ ad campaign has been far less effective than its traditional product-focused ads.

The company’s latest ad, which began airing June 10, has earned the lowest score of 26 Apple TV ads in the past year, according to Ace Metrix Inc., a consulting firm that analyzes the effectiveness of TV ads through surveys of at least 500 TV viewers. The ad scored 489 on the company’s scoring system, below an industry average of 542 and far below past iconic Apple campaigns that often topped 700.

Advertising experts have suggested that the ad campaign, which aims to focus on the experience people have when using Apple products, rather than the products themselves, may have been a forced decision for Apple, since it doesn’t currently have much in the way of new products to promote.

Writing in a Forbes opinion piece, branding specialist Will Burns suggests that the campaign is a defensive one, attempting to counter the interest generated by Samsung in a flurry of new product launches until Apple releases the iPhone 5S.

We (Apple) are reminding you of your irrational bond to our brand, the halo, the Steve Jobs effect, because we don’t have the products to back it up these days. Please buy Apple  products anyway because you feel good about the brand.

Edward Boches, a professor of advertising at Boston University, says the campaign is a risky one.

Apple was never a company that bragged about itself. In a manifesto ad, it’s hard not to come across as self indulgent. And even though it suggests the wonderful things Apple products can do, the ad lacks joy.

Some observers have suggested that the campaign is aimed at Apple’s employees as much as consumers, designed to reassure them that the company still has a vision post-Steve Jobs.

Apple’s senior VP of marketing, Phil Schiller, was recently criticized for a lack of clarity and focus in his approach.

Both Burns and Boches believe the campaign approach will be short-lived, though it’s worth noting that ad surveys are not always a good gauge of an approach, and that consumers can initially reject a style they later come to enjoy – and the consensus here at 9to5Mac is that we rather like them. We were, though, very surprised the Apple didn’t run an ad campaign promoting the all-day battery-life of the new MacBook Air. To us, that’s a huge improvement to the company’s best-selling Mac and definitely worthy of an ad campaign in its own right.

The acid test will be whether Apple returns to the softer, more values-based approach after the inevitable product-focused campaign when the 5S and low-cost iPhone (if that one makes it to the developed world) are launched.