That's a good question. I think it depends on the pricing technique.

For example, research shows that anchoring effects occur even when people are explicitly warned about anchoring before they make their estimate.

On the other hand, if people are aware of other pricing techniques, then those techniques could backfire in a negative direction. For example, researchers have found a "reverse priming effect." In other words, if people detect some persuasive intent behind the marketer, then those people are more likely to resist that persuasion attempt. So it could make things worse.

So it might have negative effect on some people (who feel it as insult on their intelligence), but if twice as many people don't notice it and are positively affected, it's still a net gain.

I think, things like this work even if you know the underlying mechanism in the pricing strategy.

As an alternate example, my realtor regularly keeps in touch with me by email, using new letters, calling me on my birthday, etc and even though I know that he is being nice mostly because he wants referrals from me (definitely not because of my winning personality :-)), I still feel obligated to give him referrals.

Likewise, knowledge of the pricing strategy doesn't necessarily make you immune to it's effects unless you consciously stop and think and able to compare with other similar services/products and are prepared to take your time.

Our software could do this for us automatically, e.g., a browser plug-in that detects prices in a web page, and automatically rounds them back up, then adds taxes and shipping.