The two enclosure tactile switches change between different ways of using the vim clutch.
The first vim clutch mode uses the ESC and a keys to clutch into and out of vim.
The second vim clutch mode uses the ESC and i keys to clutch into and out of vim.
These different modes can be combined with shift when using vim to jump to the end or the beginning of a line. The first mode with a jumps to the end. The second mode with i jumps to the beginning.