The 'Reformation' as in each and every deed, or the 'Reformation' as a philosophical/theological abstract? In case of the former, then the argument against Rome is similar unless you think Tomás de Torquemada and his merry men were in perfect Scriptural obedience. In the case of the latter, you need to explain why simony and indulgences don't have the prominence now as they did then at the time (and cause) of the Protestant break-off. You do recall the bulk of Luther's protests in the 95 Thesis, right?
It is also interesting that you talk about "Protestants" then jump to "Reformation". Thomas Aquinas and Augustine were rather "reformed" in their doctrines yet were not classified as "Protestant". The "Reformation" was an attempt to correct centuries of Roman assualts and abuses on Biblical doctrines, it wasn't until the Protestant movement where that Augustinian remnant could actually observe and speak of true doctrine without fear of being tortured or immolated by Rome's brutal monopoly of all things religious.
... before you accept that schism was necessary because of the sinful state of the church...
Why? look no further than Rome's attempt to destroy Martin Luther. Ignatius of Loyola and Francis of Assissi had no fear of reprisal from a jealous "church" because they were protected under the basic concept of the Mark 3:23 Principle. Luther's opposition to the kleptocracy which defined Rome's leadership through the sale of indulgences was as offensive as a Republican recommending that the 16th Amendment be repealed. Of course they wanted Luther dead! (Which seems to be the ultimate debate technique - agree with us or be tortured. Truth through edict and sword)
...the bible commands that there be one church, but rather that it insists that there *shall* be one church. "...
No one argues that, it is just that your doctrinal myopia (undoubtably a result of being spoon-fed filtered Roman synthesized "truth") prevents you from recognizing that the Roman Cartel has it wrong as most Protestant denominations - in that the church is not formed by simply opening doors to whoever cares to wander in, (or in Rome's case whoever is compelled to convert or suffer pain and death), but is put together by the Paraclete. This "church" needs no intermediary other than Jesus Christ, and it doesn't need to have some Dope of a Pope conjure up fresh revelations to placate the social and political expediences of the moment.
The "church" of believers isn't realized the moment they kiss the Pope's ring, it is when the Spirit regenerates. Rome would have everyone believe that they hold a person's soul in their hands. (Though Vatican II seems to have reversed that "truth" into a more moderate "truth")
...Except that's not what I'm saying. I never claimed my one post was a comprehensive apologetic....
Then you are elephant hurling, because your argument was based (and appears to still be based) on the contested concept that the "church" God had in mind was a political organization centered in Rome. To mischaracterize all of Protestantism because some low-lifes ordain a faggot as a bishop, or the American Religion follows the Roman Catholic pattern of syncretizing every possible pagan and secular belief and practice into something titled "Holy Church Tradition" - then hypocritically saying all of the Protestant movement is a sham, is not what I call a solid arguemnt for the divine perfection of Roman Catholicism.
How did the Jesuits continue within the church after being banned by Pope Clement XIV? Certainly not by obedience to the Pope. Fifth column?