The ISFjs I know aren't really afraid of conflict unless you jeopardize purposefully the relationship. Basically they tend to avoid sensitive spots by testing the reactions (I don't think they do it with machination). If you flare up when they touch a given spot, they will avoid it in the future. Figuring out this reaction is very useful in interacting with them (I have been accused of manipulation by my mother because of this "strategy", but the anger I feel is very real and thus I don't think the accusation has grounds) because eh, if you get consistenly angry they'll figure out that it's not something that should be talked about. This behaviour cannot be taken too far of course, it must be used with parsimony and only in regard to very hurtful topics. As an example, my mother never gives any opinion on girlfriends because once I broke a door in anger.

A whole different matter is when they are agitated because of an external event that they cannot control (an exam upcoming, for example). In this case is better to ignore all their reactions/lashing out, because they usually don't even remember what they are saying after the "in the zone" moment is gone.

jaja, it's not true that everybody dislikes conflict. I find debates, even very heated with insults from every side, to be fantastic. Emotional conflict is of course another matter.