Whenever I think of Delta, I think of Martha Stewart. There's always that comfortable atmosphere, where she talks to you in this soft (albeit somewhat monotone) voice, teaching or instructing you while she cooks or bakes something for you. You get this impression that she's subdued, but she's always trying her hardest to make her guests feel comfortable, so that learning or even talking, can happen.
That is the essence of Delta. Where Alpha creates, Beta uprises. Then Gamma constructs, and then Delta sows. How does it sow? By creating a comfortable or conducive atmosphere

Si

, where methods or learning can be created, optimized and passed on

Te

, so that potential for growth

Ne

may occur in the persons involved

Fi

.
Like Gamma, groups tend to be small, no more than 5 per gathering. Topics discussed to be rather "homely", where members discuss how best to make day-to-day life easier in terms of efficiency

Te:, what is the best route to get to work, how to organize day to day workflow, setting up schedules for household chores) or comfort

Si:, discussing aesthetics of home or fashion, how some foods may or may not be healthy for you). On the flip side of the coin, members may also discuss potential

Ne

relationships

Fi

[evaluating a person, discussing what this person would be like as a partner], personal growth [what are the possible paths

Ne

that a person could take based on their personal qualities

Fi

(dun dun dun does this sound familiar to you? hint: it's what this forum is all about)], or on a bigger scale, how humanity or whatever cause

Fi

could turn out

Ne

.
I was visiting my father's friend for Eid-al-Fitr/Aidilfitri, and when I arrived, there were more than 30 people in a large, cozy house, enjoying food and drink

Si

. People were split into small groups of three, with each age group mixing with theirs (Aristocratic). Unsurprisingly, the older people stuck to more practical topics such as job prospects

Te:,

), home improvement

Te:,

), food

Si

, while the younger crowd talked about who's cute, what they're like as a person

Fi

, what it could be like to be in a relationship with them

Ne:,

), possible ways to approach the person

Ne

they're trying to have a relationship with

Fi

, and sharing sentiments or personal problems

Fi

and how best to solve them

Ne:,

).
To summarize, Delta is a quadra that values a comfortable or conducive atmosphere

Si

, where methods or learning can be created, optimized and passed on

Te

, so that potential for growth

Ne

may occur in the persons involved

Fi

. The extroverts can seem introverted due to the non-socialness of the functions, however they remain extroverts because their fixation on the object itself, instead of the fields between them.