Thoughts? Experiences?

Does it challenge you to use your inferior functions more or do you just end up ignoring them and living in a fantasy land of your shared main functions?
i.e. do you become more well rounded as an individual instead of getting that stuff from your dual? Or do you become one of those couples that look like each other and never see anyone else and never confront your weaknesses? Or worse, fall into a bickering mess because the other one can't help you with your pain points?

How much worse does this get if they are the same enneagram type (mb even the same tritype) as you?

asking for a friend