How to avoid excessive column width

[dbaum]

Documentation like Controlling Column Width explains that in a table view "Columns will be automatically sized based on the size of the row content and column type." I have various questions.

1. Is there an explanation somewhere of how column type affects column width?
2. Are there techniques besides the default/narrow/wide table-level column width setting way to get a column with minimal text to be narrower, thereby leaving more width for a column with more text? For example, there was discussion in a Per-Column truncation and width control in table view feature idea about something being released about a year ago; (maybe that was the current default/narrow/wide setting).
3. Does a group heading affect column width? It looks like not, but if it does that would be helpful to understand.
   

No matter what width setting I choose (including without any group heading enabled), a "Language" column in my table always includes far more space than seems to be required.

Default

Narrow

Wide