bit confused by your sentence.

you assume, when you hear the claim that Alito != Scalia, that "he" (Alito?) is willing (unlike Scalia?) to abandon ship and be unprincipled in order to achieve ends consistent with conservative politics.

Weird.

I'd do it the other way around. Alito seldom abandons legal principles, as far as I've seen in his opinions, unlike Scalia, who frequently does. Compare Thomas, in Gonzalez v Raich, noting that the Founders would have been astounded (paraphrase) to discover that Congress could under the Commerce Clause regulate intrastate, non-commercial cultivation of marijuana. Meanwhile Scalia disses federalism, disses limited government, disses the text of the Commerce Clause, and goes along with... well, precedent. Bad precedent. Why? Could it be stare decisis? Or perhaps because the war on drugs is such an important thing for the government to be able to rely on? Sounds like Roe v Wade turned inside out.

Thomas doesn't abandon principle. He's often wrong, but that's his legal philosophy that I object to.

We must live on different planets. :)

Eh N

Scalia consistently shows more respect for commerce clause precedent than Thomas does, and consciously recognizes their differences on the issue of stare decisis.

However, I'm doubtful on either of them being super-principled in certain cases. For example, neither a textualist nor an originalist reading of the Constitution seems likely to me to have turned up their concurrences in Virginia v. Black (cross-burning case), where both said that the impact of a burning cross on African Americans was so negative as to overcome the First Amendment as well as the need for prosecutors to prove that the cross was burned with the intent to intimdate.
Nor would the perceptions of the 14th Amendment and prohibition of race-conscious state action that they exhibited in the affirmative action cases seem congruent with Johnson v. California.

I briefly thought that perhaps Scalia is just super-troubled by drugs, but he's carried his vote in cases that involve drugs (Oregon v. Smith) to cases to which he ought to have been pretty sympathetic, like a Catholic church's desire to expand (Boerne v. Flores).