Should have read this first before posting. I though IV did ZTG without error and if I recall it does exactly that, makes a tiny little break. It’s the software doing a work around rather than the designer having to do it…I prefer that.
That opens a big question…which side of the face should the software “adjust” to? Outside and break the face or inside and leave it whole? Inventor breaks the face.
I wouldn’t call it a flaw. The software recognizes the condition and tells you. It just doesn’t allow you to create that condition. Inventor recognizes it as well and makes a predetermined decision to offset it a small amount.
Isn’t every corner, edge etc essentially ZTG? At some point doesn’t the material in the model trail off into infinity? seems to me that all that the software does is say "Material stops at this point and ends at this point and does so with in the precision of it’s calculation ability.
At some point you hit zero or less and you stop. I don’t see why ZTG of two intersecting features should be any different. You have material all the way up to this point and you have a break after that, with in the precision of the software. If you land exactly on zero you make the decision whether zero is a break or zero is geometry.
Isn’t this already done via some mechanism limited by the precision of the software? As I mentioned in the other post this same thing has to be done with any surface, corner edge. At some point you exceed the precision of the software and you have to round the number…up or down, break or no break, is material here or not.
I would agree it’s not a flaw. Maybe a preference. I would much rather have a program that is consistent that says “If you’re directly on the line we will always break it” than have to force the designer to decide and or worse yet actually force the designer to design to the wrong number.
If that is the case then, if the part would be manufacturable - ZTG would be water tight, is that a correct way of looking at it?? 
Question for those who think ZTG exists: Can a light beam pass through a ZTG area? Yes or no?
Also, ZTG is different than a theoretically perfect cube. ZTG cannot even be accurately displayed on a screen (is it transparent or opaque?), but a perfect cube can. CAD does not have tolerances. (Please put down that pitchfork, it makes nervous.) CAD does truncate decimals, but it does NOT just throw geometry out there willy-nilly and call it perfect.
I’ll answer your question with a question. Is Schrödinger’s cat dead or alive?
I really don’t think one way or the other is “correct”, whether there is an infitesimally small thickness of material there or an infintesimally small gap. The software would have to pick one or the other…I don’t really care which. Having the “error” of having a gap when you want a piece of material is more acceptable to me than having a hole at .0000001 when it should be at zero. Again probably personal preference.
I see this as a simple question of “Does material exist or does it not exist”. You can’t have material and not have material at the same time. Thus the discussion of ZTG is not about does material exist and not exist at the same time, but rather what choice/Truncation/Rounding does the software do when faced with “0”.
The same question exists with every piece of geometry. At some point the software has to say “Nope, no material here”. So is there material at 1.0, yes, 1.00, yes, 1.0000000000000000000000000000000…no idea because we rounded at the 9th decimal place and whatever the rounded number is that determines material or no material. The same thing applies to 0. Is there material at .01, yes, .0001, yes, .0000000000000000000000000001, no idea because we rounded at the 9th decimal place. In this case it would be rounded to zero and if the software says zero has material then it does, if it says it doesn’t then it doesn’t.
One would think zero would mean it doesn’t, which is what IV does, creates a break.
. . . or one for us simple-minded non-engineers. Where was the man when he jumped off the bridge?
On the bridge? No, that was before he jumped.
Okay, he was in the air. No, that was after he jumped.
matt There may be an issue with this page because most images are blank except this one which shows up as an abstract painting…!
It is actually quite pretty 
File-corruption on the server???
What bothers me is that I can create two individual bodies without issues, but I can’t merge them into one body:
Yeah, this was an old issue we had early on. I’m getting those cleaned up.
Which illustrates why this is more of a software coding issue than it is a theoretical impossibility issue. It’s nothing more than deciding how you want to deal with the numbers, make it a gap or make it material. Making it a gap or boundary makes the most sense. Two parts put together with a boundary with zero space between would be the same as “Zero thickness” where a boundary was placed at the point of the ZTG.
Think about the term zero-thickness.
Q: What is another way of describing zero-thickness geometry?
A: Hole
In other words, zero-thickness geometry is an oxymoron, which says nothing about CAD functionality. There are good reasons why we spend so much time pleading for this functionality, but the concept is nonsense.
I feel my brain on fire.
So what about Mike’s situation now.
I thought it was one of John’s Pictures. 
Can a plugin be written for this? so a trick to disable this feature.
Yes, but not in this application.
https://en.wikipedia.org/wiki/Quantum_wire
Carbon Nanotubes are one molecule wide. Atomized silver can be absorbed into a carbon nanotube to create a 1-atom wide nanowire, as accidentally discovered two months ago by university researchers. These 1D wires are intended for use in nanoarrays.
1-dimensional objects do exist, and you can google that term for lots more than you probably care to understand. That fact is irrelevant to CAD design, as it is not intended to apply to a quantum scale.