If a letter was cut or broken (nifsakah), when is it valid and when invalid, and does covering adjacent letters affect the test?

Synopsis

If a letter was broken after being written correctly, the test is whether a child who is neither genius nor simpleton can read it. No need to cover surrounding letters. But if the letter lacks its proper form entirely, it is invalid even if the child reads it. The letter must have been written correctly initially.

Early Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

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