DD:
I would consider one as a brother in Christ who had completely backslidden.
I'll go further - I wouldn't deny any as a brother, since there is no way to be sure that an individual isn't nor ever will be of the elect. Contrawise, unless a brother is on fire for Christ, by such means that your spirit resonates with his and gives you inner testimony, how can you be sure of any? By their fruits? And yet even the hypocrite can emulate outer works and, besides, that is exactly the thing you appear to show concern for.
Now you may immediately object, retorting that I'm being a Universalist, but that I would deny. I think scripture is clear that there is at least one "son of Perdition".
I would also attest that there are likely some Arminians who are far closer to the throne of grace than I'll ever be, for all my passion for Christ and acceptance of Calvinistic doctrine.
You are correct to say that legalism is hard to overlook, in fact it's outright galling, especially when it's rammed down your throat. However said legalism is just as prevalent in Calvinistic circles as it is Arminian ones. Therein is the greater love and grace required.
I find it ironic that sometimes it is easy to love our enemies, yet our brothers can be a more difficult affair - as the Apostles attested to in their exhortation!
Tell me, is it "doctrine" that saves, or grace?
Is it the written word, or the love of Christ?
Is it right religion, or a living relationship with the Divine?
Is it the works (or lack thereof - with right or wrong motive), or the spirit of God within, that constitutes a brother?
Btw, you've just hit on a subject that I am extremely passionate about!
If you can't feel that through my written words, then we ought to discuss it sometime
Didier:My dear friend you may "interfere" any time you wish.
Interchanges with you are always a pleasure!