Feud with INTPs? I really quite like INTPs and INFJs, I find that both bring interesting discussions to the table. They are one of the few types that actually think deeply, well INFPs and INFJs more so. INTPs seem more interested in concrete subjects. I don't typically spare anyone my wrath because I don't have any wrath to give. It's kind of a misunderstanding that INTJs are always angry, if anything we are very passive, quiet people. The only time we are ever "aggressive" is when we are seeking or trying to point out a truth or untruth. Any other case may be due to someone pushing our buttons more than we can stand.
If an INFP says something that isn't truthful, I will point it out. I don't care how upset it makes them. Sorry, the truth is not going to change because you feel bad. I try to do it in a tactful and calm manner, sometimes INFPs can be a rash. Something may set them off and you will never be able to shut them up. Best approach is to simply shut up completely and let them rant. They will eventually realize what an idiot they're coming across as and apologize. For the most part though, I find them much easier to bounce ideas off of. They're open minded and accepting of facts. They can be sentimental but they can push it aside for the sake of looking at something in a different way. This ability to look at something from all angles, gives them this ability to accept another point of view.
Ironically, one thing that bothers me about INFPs is the fact that they always have to play the devil's advocate while having a discussion. I don't really care how the other side feels, I care about what is true v what isn't true. Many times they want to try and put themselves in the shoes of everyone, this is how the try to find the truth. I find this interesting because it suggests that they share a common goal with INTJs. They are seeking truth and I think we can bond and discuss things in ease due to this quality.
I find INFPs much easier to talk to than any other type. For one thing they actually listen to my points and seem to take them sincerely. ENTPs are pretty much interested in talking mostly about themselves, if you actually get a chance to say five words it's a miracle. I love you guys, but damn...every time I start a conversation it ends up in 90 different places to the point where all of my arguments are off topic.
ENFPs are all about taking sides, which tends to take the discussion into wing but territory.
ENFJs are also all about taking sides, especially if it comes to causes. ENTJs are usually pretty easy to talk to, but I wouldn't say they're very good for the kind of depth you'd get from an INFJ or and INFP.
SJs and STs....LOL don't even get me started....occasionally an ISFJ or ISFP is willing to listen to your crazy ideas, usually because they are a close friend and know you to be level headed.\
INFJs tend to be very wishy washy and if you don't agree with them, then they don't seem to get much out of the conversation. It could run in circles for days until you're stuck in an endless loop. They seem to understand your point, but respectfully disagree. I find that they will go as deep as INTJs will into an issue and can analyze patterns fairly well. The one thing that may be lacking would be facts, stats, and data. Overall, I enjoy talking to them because the conversation could end up anywhere. They seem unafraid to delve into certain subjects others wouldn't even think of.
INTPs are interested in concrete subjects, facts, statistics, but they are not always going to analyze those statistics in the same way an INTJ or INFJ would because they don't see patterns in the same way. So they may try to argue against your point, regardless of whether or not it's true. The two may butt heads over this, but it rarely ever happens. Usually we tend to be on the same page because we are generally collecting the same data and stats. Oddly enough, we may actually agree with each other, but because we're coming from two different places, we can't see it. So there's a pointless argument for no reason...
INTJs are most interested in what is true v what is not true. It has nothing to do with feelings or even rationality. I know INTJs are always claiming to be rational, but what we really want is the truth. If someone says something that we know to be untrue or worse, tries to spread this untruth, we are on their ass faster than white on rice.