I am not saying I don't hold to a trinitarian belief
I'm not saying I do... What I am saying and I think agreeing with you about is that textual criticism may be interesting but takes time which is better utilised on establishing whether the disputed text is in line with scripture or not.
I really do think we are actually agreeing that textual criticism is not the best way forward.
We know there were forgeries in the time of the apostles and Paul contended about them:
2Th 2:2 That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word,
nor by letter as from us, as that the day of Christ is at hand.
(Come to think of it, 2 Thess 2 may be an interesting context...)
Are those forged letters in our Bible? If God inspired scripture in the first place, why should he not have overseen the compilation of the scriptures that we have?
And if, of all references it doesn't matter if 1John 5 is actually inspired or not, (because we should be forming our understanding on the rest of scripture), then textual criticism is hardly going to be profitable regarding any other part of scripture.
(For the record, I do personally think that section in 1John 5 is most probably spurious and in a public reading I omit them. )
Should my belief about the divine nature rest on those few words? I don't think so. Should anybody else's? I don't think so. And that is something else I think we are agreeing about.
Eph 5:26 That he might sanctify and cleanse it with the washing of water by the
word,
Eph 5:27 That he might present it to himself a glorious church, not having spot, or wrinkle, or any such thing; but that it should be holy and without blemish.
It is the word of God that achieves that, and I believe the word we have is sufficient to achieve all of that by itself. In which case, it is textual criticism that is spurious and we simply don't need to worry about any particular part of the scriptures that we have detracting from the overall message.