Well if I may encourage you to do so, I would say, fear not the Ring of Fire, jump through it calmly and optimistically as doing so will serve as practice and increased familiarity.
To strip away the metaphor, what I kind of mean is that communication is probably the most under-estimated skill any human can have. That is, it would take, like, a million years to master communication, and so, all of us will need to work all our lives on getting better at it.
Sure it's great when communication flows smoothly (e.g. without misunderstandings), but if you hit a bump in that road, just chalk it up to learning experiences and carry on. Most of us assume we speak the same language, and we actually all have our own unique dialect. So, sometimes, developing a smooth understanding with a newly-met person is rocky traveling in the beginning.
This could really turn out to be relevent, because you could meet the woman of your dreams, and find that (drat!) you have a heck of a hard time trying to communicate clearly with her. And misunderstandings will cause hurt feelings at times. So you have to be patient in learning each new person's dialect. It's all good practice for when you (hopefully) meet the perfect lady, and need to be able to communicate with her skillfully.
In my experience, the most common bump in the communication road is assumptions. It's so easy to think, "Well of course the other person knows this is what I mean," but lo and behold, they thought you meant something completely different. So it's really important to get confirmation and make sure the other person understood exactly what you said.
It can be a pain to have to agonize over every word, wondering if it's the right word, or if it will cross the chasm properly to the other person, but it's a necessary part of the process of learning to communicate better.
I apologize if I went overboard with my sermon here, I only meant to encourage you that sometimes the Ring of Fire can be a good thing, and above all please don't feel like you somehow "dropped the ball" if someone needs you to explain something a little more.
It sounds to me like one-on-one sex (just as a threesome) would be okay with you right from the beginning of your relationship with this "hypothetical lady" we've been speaking of?
I am hearing that you have your fond hopes/dreams/fantasies for the future, but that you are cool with being flexible even if a "perfect triad" isn't quite what you end up with. That's a good sign.
And as I said, the most advanced polyamorist/non-monogamist in the world is still a newbie when it comes to communication. We're *all* newbies in that regard. So have patience in your Polyamory.com conversations; we are, after all, such a huge group of complete strangers all "mashed together" in a chaotic mass of diverse expressions and distant perspectives. Truth is, it's amazing we function as a forum as well as we do. It's like picking two strangers off the street and asking them to pose for a picture in some way that suggests they're intimate friends. Sometimes pretty darn awkward at first.
Stick with us, and we'll get all the wrinkles smoothed out, I promise.
Love means never having to say, "Put down that meat cleaver!"