DaMoshe and mw13:
Let’s be very clear, since it should be offensive to any Torah Jew when they see anyone trying to adulterate the Torah and claim that as authentic.
The gedolim have declared unequivocally that MO is not a valid derech. See Joseph’s post linked on the first page for some quotes. There’s much more, though.
For example, Rav Shach strongly condemned (in writing) Rabbi Soloveichik (“the Rav”, in MO terms), stating specifically that his words (related to Zionism) were heretical to the point that it is shocking to even see this kefirah. The Imrei Emes wrote that Rabbi Kook, despite his great knowledge of Torah, cannot be a valid transmitter of the mesorah.
Both Rav Shach and the Imrei Emes wrote about these men (respectively) that their “ties” to the philosophies and movements of the time (e.g. Nationalism) is what caused them to write these terrible things, to project these heretical philosophies as Torah.
Since Rabbis Soloveichik and Kook are essentially the sole underpinning of MO theology, it follows that MO has absolutely no “mesorah” (including from Rav Hirsch whose views are also very much opposed to these heresies).
None of this should, CH”V, be taken as casting negativity on MO adherents who don’t know any better; they are likely simply following the misguided theology that they learned in their institutions.
But the fact remains that MO’s “derech” is absolutely baseless, no matter who professes it.