Well I consider Ms HB "shoot from the hip" type of lady but I don't consider her tactless. I also say what I mean. I'm not 100% (but who is?) but I'm pretty much up there in the 90's range.
On this point, I'd have to respectfully disagree. I'd say you're in the low 80's and from what I've seen of Ms. Heartbeat over the years, I'd rate her an 85. It has been my experience that people who break the 90's mark (and the rare few who are at 100) don't care a whit how the message sounds. After all the "truth will set you free, no matter the delivery." For example, let's say your friend asks you how they look in an unflattering outfit. They want your honest opinion.
80's-"I think you would look better in XYZ outfit. That one just doesn't have the right fit."
90's+"I think you look like a hot mess in that and I would be embarrassed to be seen in public with you with that on."
I'm quite nice about it, but I do call it. What I've observed is that when you say something people don't want to hear, they'll turn defensive and use all manner of methods to divert, distract and flip the script rather than focus in on what was said. (Especially if they don't like the message that was aimed at them).
Nothing like a good defense. One can "shoot from the hip, and have tact in doing it. Maybe you just haven't been around people who have done this. I guess that's why they have that old saying, "Truth hurts". and "kill the messenger"

Nobody likes to be "called", when they are in the wrong about something and sugar coating it until you get a cavity won't make that pill any easier to swallow.
People also tend to simplify complex issues and categorize people in neat compact boxes. It's simply human nature. Yes, one can sugarcoat things to such an extreme degree that the underlying message is lost, but anything can be taken to an extreme, "including shooting from the hip" with an AK-47. Moderation is the key. As another aside, the skill of diplomacy is, at it's heart, finding the just the right mixture of sugar and truth to negotiate complex problems between individuals and nations.
I'd also like to add as an aside, that in my experience dealing with people who don't speak their mind, who are not forthcoming (And again you can be straight and do it nicely and tactful,) tend to be passive aggressive in varying degrees. When they don't say what's on their minds, they also can't take even the lightest amount of criticism. These people walk around quietly seething inside, they are like a pressure cooker with all those emotions boiling below the surface until something sets them off and then THEY GO OFF!
Once again, extremes tend to lead to the problems you describe above. Just like those who cannot speak their mind can be passive aggressive, I have found that those that always speak their mind can be overbearing, arrogant, and downright pains to be around. Plus, they also tend not to do well with criticism (having an ego the size of Jupiter tends to do that). Does that mean everyone with those traits are like that? No, of course not, but it is a recognizable trend.
One thing Jada said that stood out with me, is that she told her husband that if he had a problem, let her know about it, even if it's hurtful. She'd rather that when the cut comes, to go ahead and cut cleanly, because those are the types of cuts that heal. She said it's those jagged scars that pulse and fester.
I agree that is good advice. Just be wary of "hemophiliacs", those individuals that no matter how clean you try to "make the cut" they gush blood as if they were in a Tarantino flick and they never properly heal.
I also think most people (men and women) who persistently don't have a clue have learned defense mechanisms that tune out other people's feelings They've walled themselves up to a certain degree. The only feelings that matter are theirs, (unless of course there's an advantage to "tuning into others",then suddenly they let down that wall.

. In my experience, people I've interacted with like this, are self-centered to a degree.
I've interacted with individuals like this as well, they're called sociopaths and it's best to just cut your losses and steer clear of them.
Maybe she has done something to cause me to lose all respect for her, therefore causing me to dismiss anything she says.
I wonder why people would be with someone they hold in such contempt. No relationship can succeed long term under those circumstances. Yet I know a lot of couples who obviously feel this way about their SO. I've seen how they interact. I've seen the looks, the slightly curled lip, (when they didn't think anyone was watching.) The condescending, supercilious attitude in the way they talk and deal with their SO. It's that 'jagged cut" Jada mentioned. I say if either partner can't get over whatever feelings they are having towards their SO that is causing them to act that way, then it's best to break up. I was on the receiving end of treatment like that from a SO, not so much for anything I'd done to him, but he just thought he was better than me because of "who he thought he was". I couldn't take that long term.
This is easier said than done. There are many reasons that people stay together despite the contempt they feel for one another. Political expediency (aka the Clintons), perhaps they're there for the children, perhaps they are strongly mired in tradition ("till death do us part") and, as the the saying goes on the male side, "sometimes it's simply cheaper to keep her".
Now that being said, the "me" that I was using above was simply to frame the proper context to answer your hypothetical situation. I personally would not interact with someone I have no respect for unless I was forced to.