The Acid3 test tests against various standards that are not yet actually standards, as they're in draft at the W3C, and not yet agreed upon and and approved. Because of this, Hodge states that it does not make sense to fully support Acid3 just yet. "The concern Microsoft has is that if we burnt [draft standards] into Internet Explorer 8 and passed Acid3 with 120 percent and then deploy it on so many machines, especially in the enterprise, [we have made draft standards de-facto standards] when the W3C will then want to innovate on the [evolving] standards," Hodge explained, "We passed Acid2 with 100 percent which tests against recommendations from the W3C. Acid2 is about recommended standards, standards that are locked and loaded."
He went on to say that Microsoft learnt its lesson with Internet Explorer 6. "Our learning comes from IE6. With IE6 we adopted some non-recommended standards and interpreted them in a certain way. The end result of that has been painful web development."
It surely is an interesting view on things, but it's also a flawed one. The standards tested by Acid3 might not be official standards just yet, but with Opera, WebKit, and Gecko all working towards supporting it, Trident could've just followed and make it the standard. This would've certainly earned Microsoft some good karma, something it could use in the browser market (what, with IE bleeding market share like a decapitated bunny).