This is something from the topic about whether or not the forum is going downhill, but I want to expand it into a larger conversation about the nature of Fe, and how it is different based on what IP element it is blocked with.
The intuition at play here is that Fe as blocked with Ni (and in Se-valuing individuals) looks different than Fe as blocked with Si (and in Ne-valuing people). Staying on topic or not isn't really related to any function, if anything it's related to both thinking functions. But Fe blocked with Ni is going to be more grandiose. It has more interest in making the passion as large as possible because Ni is interested in ideas that are as large and as abstract as possible. Fe blocked with Si is going to be gentler. It's going to poke rather than prod. It is concerned not with making the passion as grandiose as possible, but with making the atmosphere as pleasant as possible. It doesn't seek extreme emotional atmospheres as Beta Fe does. It seeks emotional atmospheres that complement a positive internal state.
The fundamental problem here is an overidentification of Fe with "emotion." Certainly, Fe is about changing internal states (internal dynamics of objects), and a changing internal state is often identified as an emotion (as opposed to more habitual internal states, which Ne is concerned with, such as being a "grumpy" person, or a "happy" person). But changing internal states aren't always big noticeable emotions, because big noticeable emotions wreck Si equilibrium (you can't reach an equilibrium if you're always bouncing around from ANGER to SORROW to GRIEF to RAGE to JOY). Rather, changing internal states, when informed by a concern for external dynamics of fields, rather than the double internality of Fe and Ni, involves making the atmosphere more comfortable emotionally. Smoothing out extreme emotions, working in precisely the opposite direction.
Of course, this is just in the abstract. In practical terms, the two "versions" of Fe are still quite similar, but hopefully this suggests some of the underlying difference.