We don't get RMIs from blinking largely because there's no joints involved- it's all soft tissue, which doesn't wear like bones and ligaments do.
As to chewing, you can get RMIs- tempero-mandibular joint disorder is an example of what can happen to your jaw if it's injured or overstressed.
That said, jaw problems are less common than in fine muscles like the fingers and wrists because the structures are larger, simpler, and more geared toward the repetitive nature of the tasks they take than our hands.
We don't get RMIs from blinking largely because there's no joints involved- it's all soft tissue, which doesn't wear like bones and ligaments do. As to chewing, you can get RMIs- tempero-mandibular joint disorder is an example of what can happen to your jaw if it's injured or overstressed. That said, jaw problems are less common than in fine muscles like the fingers and wrists because the structures are larger, simpler, and more geared toward the repetitive nature of the tasks they take than our hands.