I'm getting off the point here, but if you see differences in yourself with a lot of typical ISFP descriptions, yet don't type as T because you're mostly cool to people, you should look into socionics. I think I suggested it once. There are still big differences with ISFps.. if you say you're people oriented then you are more ISFp probably, but anyone who's got a smile or something isn't an F. The colder ISTp that people are probably more used to is just a logical subtype. The sensory type is the more laid back, even stylish or artistic out of the two, which could get them confused with Fs.
[ISTp-S]
Aesthete, disposed to obtaining pleasant sensations. Is considerably more gregarious than the initial subtype. More optimistic, but less operational. Sybaritic epicure. Dresses with taste, chooses clothes that emphasize their good looks, selects clothes according to colour. The sensory subtype is modest and non-demonstrative, constrained and polite, obstinate and uncompromising in regards to upholding their interests. Give concrete, logical reasons, rather than far-fetched ones, when explaining themselves. From time to time become thoughtful and isolate themselves from friends in order to plunge into their problems. Restrained in dialogue, they are laconic but at times try forcing a smile if they feel that there is intensity in the conversation. Dress with taste, like original, but modest, items of quality; watch over their health and figure: an aesthete. Enjoy manual labor, they are careful, laborious, patient and persistent; if in business will tirelessly improve production – material or intellectual – though sometimes they require a change of employment. Gestures tend to be graceful and lazy, smooth and thus confident in exact movements. Gait appears a little bit weakened and elastic; do not like feeling rushed but, at the same time, are not sluggish; may seem a little bit haughty.
[ISTp-L] Outwardly businesslike, a little severe, cold and unapproachable. A realist and skeptic, distrustful of novelty. Will always avoid useless matters, due to pragmatic nature. Very dynamic and technologically effective, Can extract the maximum of benefit even from tools. Their production is always foremost and will stand up to any competition on the market. Clothing is restrained, conservative, and they prefer a sporty, technological style.
The logical subtype prefers to maintain a distance. Are very independent and proud; act for their own convenience. In conversation may become ironic but can also become affable and interested if shown sympathy/respect from the interlocutor. When they become aware of having had offended someone they show regret, soften themselves and apologize calmly. Behind their external inaccessibility lies vulnerability; are impatient and mobile, love constant changes and new impression, are active, efficient and careful. Disdain discomfort in all situations and are therefore prone to correct/repair/adapt everything for the sake of convenience. Reliable and punctual, are exacting towards themselves and others; they behave with cold advantage but still may become emotional. Their behaviour is unpredictable and characterized by unexpected transitions from cold contemplation to active action. Gestures are impulsive, resolute. Gait: fast, measured.