Setting aside the theoretical objections to Solomonoff induction (a priori assumption of computability of the hypotheses, disregard of logical depth, dependance on the details of the computational model, normalization issues), even if you accept it as a proper formalization of Occam's Razor, in order to apply it in a formal argument, you would have to perform an uncomputable calculation.
Since you can't do that, what's left of it?
Besides noting that there are computable versions of Kolmogorov Complexity (such as MML), in your parent comment you contrasted the use of SI with using Occam's Razor itself.
That's what I was asking about, and it doesn't seem like you answered it:
How do you use Occam's Razor, what formalizations do you perceive as "proper", or if you're just intuiting the heuristic, guesstimating the complexity, what is the formal principle that your intuition derives from / approximates and how does it differ from e.g. Kolmogorov Complexity?
r/HPMOR readers on heroic responsibility - not the OP, the comments. Holy snorkels this is good.