Sergeants, from what I recall are members of the group that are not noble, that's it. I don't think it includes temporary assignment. I know Master at Arms is a higher rank of sorts, so that's out too.
From what I read of the rule and other sources, it appears they all took the same vows and followed the primitive rule, in theory, to the letter. I'd say, there's a guarantee that there was a couple who didn't (after all how many people wash out, for whatever reason, of a 4 year commitment in the military today counting basic?) but those that washed for dishonorable reasons I feel didn't fare too well. Even those that were temporary members, they took the vows, whatever children they had prior to it, family, wife, etc would be stripped away for the time period they served. I'm going to go through my sources, I have a TON of primary and secondary texts actually, and I'll try to quote what I just said.
I know on Mr. Metz's flikr, he has a picture of him in a Templar kit, and the caption states that since he's married he would in theory be a _____ Templar on temporary duty.
Being a secular member of the order could work, but that'd be splitting hairs for the most part. We've already agreed I'd do the persona when necessary: IE when I see people prancing about with long hair and wenches on their arms while wearing the white habit and red cross, or when people ask me, or especially when people seem interested in knowing the archaeological and histiographical data. This kit is more a labor of love than anything, I'll still have a secular kit as well, making a sleeveless surcoat with ailiettes is the least of my worries
that and that kit can have a fancy helmet, sword, etc etc etc, more excuses for prettier things! Hence why I've never joined a real order
Sir Edward,
good point about having children prior to joining, didn't think of that one. But as you said, it'd be rare beyond rare. I hope it doesn't matter in whichever court hears this FUBAR boondoggle out, the Templar Order had acquisitions, not the individual knights. When the order was absolved, all those assets would have been dispersed at the Church's discretion, and the brothers would have been absorbed into other orders, I'm sure, happily.