Burnt Wire

The fusible link will save the main circuits from abnormally high current flows. High as in 100 amps or more.

It will not not protect the small branch circuits with 16 or 18 ga wire.

It may or may not protect main circuits from extended periods of high current.

Here's the type of damage that will occur when 40 something amps runs through the main circuits for more than a few minutes.
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And this (black wire) damage was at least in part due to loads varying between 30 to 40 amps for 20 minutes.
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