I think we can never filter out the situation dependence in this, and there will always be "grey zones". However, omission is _always_ potentially problematic, and openness, maybe rather transparency, is always an ideal. But I don't think concentration on lots of rather irrelevant details may have so much to do with openness, like "you won't even tell me what kind of massage oil you used on her".
The issue is how to approach that ideal. A too direct approach may not always be the best, if that creates misunderstandings or provokes reactions that are not really in proportion to the underlying problems. Dick size comes to mind here as something the other partner is likely to misinterpret, given the "data"
Also, if one partner feels very insecure, the "complete truth" about how much another partner means to you, can be rather destructive - even if the insecure keeps asking about it, it may be better not to give out the whole picture at once. Because it is likely to be misunderstood - maybe he loses all confidence in himself and your relationship, backing out. But in such a case, the problem has to be addressed, just shutting up to avoid "hurting feelings" etc is not an option.
To me, the question is: In the big picture, is my action contributing to us approaching openness or losing it? And how do I work on my own reactions, making it easier to be open towards me?