You discuss the situation when people do not know about the Socionics. I'll add what may change when they know the typology and IR theory, how this may affect the relations. Including the shifting to lesser matching with the theory side.
1) strengthening. When you know the types correctly you pay more attention to types related effects, - may better to feel and to use them. So duals may create better couples when know they are duals. Conflictors may get lesser interest to keep the relations and do lesser efforts for them, as understand that with duals may be much easier.
2) compensation. People when know about bad IR may apply more efforts and with more efficiency, with the using of types theory. Sometimes people may overestimate the good IR and do lesser efforts for good relations than is needed or choose too worse pair by non-types traits, to get worse result than when they'd did not know about the types. Though the importance of non-types factors is relative, as effects of types mb strong anyway, - IR to give effects what they should without significant reduction, it's mostly sum situation changes, while feelings/relations be good in IR part and just harder in other parts.
3) self-making. If types were incorrectly identified, then with thinking better IR people may value such relations higher and do more efforts to do the relations better. With thinking worse IR - the relations may become worse, than could.
4) worsening. If types were incorrectly identified this may lead to higher misunderstanding between people to create more problems. People may reject good pairs as think IR are worse or are not sure in the types, or to pull bad pairs as think IR are better. To the same may lead as people may underestimate the importance of non-types factors.