i like this one:Sola scriptura teaches that the Scriptures are the sole infallible rule of faith for the Church. The doctrine does not say that there are not other, fallible, rules of faith, or even traditions, that we can refer to and even embrace. It does say, however, that the only infallible rule of faith is Scripture. This means that all other rules, whether we call them traditions, confessions of faith, creeds, or anything else, are by nature inferior to and subject to correction by, the Scriptures. The Bible is an ultimate authority, allowing no equal, nor superior, in tradition or church. It is so because it is theopneustos, God-breathed, and hence embodies the very speaking of God, and must, of necessity therefore be of the highest authority.
Hi Justasking4 !
You’re dealing with aspects of this definition of yours with other posters. The point I’d like you to focus on, is about how we properly understand Scripture, ie “our only infallible rule of faith”
As you know, that leads to the issue of “perspicuity”, which, in definitions other than yours own, is explicitly dealt with. I guess
we agree this issue is essential and unavoidable.
In
www.apuritansmind.com/FrancisTurretin/francisturretinscriptures.htm
we can get a central passage on perspicuity. The author, Francis Turretin (aka François Turretini ) is a favorit classic reformed.
Quoting him, from a reformed site, I will hopefully not be considered as building a strawman.

VI. It is not a question of a perspicuity that excludes necessary means for interpretation, such as the inner light of the Spirit, the attention of the mind, the voice and ministry of the church, lectures and commentaries, prayers and vigils. We acknowledge such means are not only useful but also normally are necessary, but we want to deny any obscurity that keeps the common people from reading Scripture, as if it were harmful or dangerous, or that leads to a falling back on traditions when one should have taken a stand on Scripture alone.
VII. The question therefore comes to this: is Scripture so understandable in matters necessary for salvation, not with regard to what is taught but with regard to the manner of teaching, not with regard to the subject [persons], but to the object [Scripture itself], that it can be read and understood for salvation (salutariter) by believers without the help of external traditions? The Roman Catholics deny this; we affirm it*.
What is Turretini referring to here as " external traditions" ?
You can get he’s speaking about Sacred Tradition, since he could not say that the Catholic Church affirms human traditions are necessary to understand Scripture.
In other words, he tells us there was no need, after Revelation, of passing the way to properly understand Scripture, together with Scripture. All what we need of Revelation is the written word.
This is regarded as the real point. Revelation, in a reformed view, left a text, but not a CONtext in which to properly understand it. It was unnecessary, the text itself gives everything necessary for its own comprehension.
Note anyway that Turretini does appeal to traditions in paragraph VI. It is manifest that he believes that traditions within his calvinist denomination ( ministry, sermons, vigils …) are strictly scriptural.
These are presented as necessary for the individual believer to properly understand Scripture. In other words the position IMHO can be summarized as "Scripture is properly understandable ( all what we need of Revelation is the written word) in matters of salvation with the ordinarily necessary guide of the scriptural traditions developed within my own denomination. ".
Some problems coming from this exposition:
“If we cannot assume a calvinist tradition was always there, does that mean it was ordinarily impossible for believers living before Calvin to properly understand Scripture ?”
More generally,
" What is the merit of any definition of the “perspicuity of Scripture”, when it is assumed by those propounding it that the real message of Scripture ( therefore Jesus’ message in a SS perspective) had been essentially lost, and had to be restored after centuries and centuries" ?
A “perspicuous” Scripture, in this view, had not been correctly understood for a millennium.
I hope my point here is …perspicuous.

and Justasking4 and every protestant brother here will consider
what the real pausibility of the concept of “perspicuity of Scripture” is, in its different versions.
And perspicuity, IMHO, is explicitly or implicitly essential for the doctrine of SS: SS cannot stand, if “perspicuity” falls.