Having been directly involved with the creation of Kat's sheet, and not being in a recovering state, I feel uniquely qualified to respond to at least some of the issues presented here. In fact, both the "APV" and "Safe Pass-Through" terms (along with some others) were discussed specifically during the creation, knowing full well that someone would raise questions.
So while Kat sleeps off her Duggan's, allow me...
Regarding "Safe Pass-Through", we discussed using "Recommended Pass-Through" instead, but decided that it wouldn't avoid controversy either, and would only make the column wider (with little or no value added). The reality is that this is a very personal definition, and people should really do enough homework to know whether or not it's for them.
For me? NOTHING fits the definition. I simply won't do it, outside of one very unique mod that (a) almost nobody has, and (b) I know for a fact was designed to handle it. It does not use USB, but a proprietary connection instead.
But for the purposes of the sheet -
- If the technical specs included warning/advice against doing so, it's a "No." For example, anyone who's ever purchased a Mamu mod, with a lipo battery, knows that she was VERY CLEAR about NOT using it as a pass-through.
- Contrasting the above statement, if specs identified it as a "Pass-Through" device, it's a "Yes".
- Obviously, rows left blank were/are undefined*.
* With no guarantee that something hasn't changed, and subsequently been missed, since its entry to the sheet.
Certain assumptions had to be made, with the knowledge conflicting information existed (and would probably be presented at some point). Given that many vapers appear to look for such opportunities (peruse threads if in doubt), this was almost unavoidable.
crxess & Richajho, you've both been around long enough to know that conflicting definitions exists for many components of our vaping world. In fact, there are many who would argue with crxess' definition of Passthru, eliminating "B" and retaining simply "A". The fact is that we're still somewhat in the Wild West, defining many aspects of what will (hopefully) become understood as time passes.
Regarding "APV", yep - that's a sure fire argument, almost without fail. Advanced Personal Vaporizer. Nebulous much? Who's to say....
But it is a commonly used term, and almost all of these devices can be found in said category when shopping through a large percentage of vendor sites. Anyone intent on arguing the use will find valid reasons to do so, and all I can do is sigh. We all know what the intention is, don't we?
BrotherBob's question was a good one, and should be asked. Kat knows my feeling on the subject, and happens to be in agreement. Anyone deciding to bring a device to their mouth, that is connected to an electrical circuit, probably should do a bit of homework before doing so. Just because it says you can on a silly little spreadsheet doesn't mean that you should (see "technical-reference" video at end-of-message).
The sheet was designed to consolidate information, some of it anecdotal, related to the fastest-growing trend I've experienced since beginning this vaping thing. I felt it was unmanageable then, and I continue to think so. Stuff's coming out WAY to fast to keep up with, but I give Kat credit for doing her best.
If it was me, I'd have opened the dayum thing up for editing, a long time ago, and said, "Have fun y'all! I am outta here."
I hope this brought at least some value to the conversation.
And I leave you with the aforementioned "technical reference" video. Is it safe to use as a pass-through? Heck if I know. I'm just a French model.
That means a great deal to me, in spite of the fact that the colleced data is fallible. Please, if time permits, come and shed some light on the actual thread. Those of us there, are...... hmmmmm...... "available". 
