The essence of Taproot is to improve privacy and efficiency and it's most efficient when you are using script path or non. Though using what you mentioned above is correct in a traditional of K of n scheme, But not quite the most efficient in Taproot.
In taproot rather than using all the combination as seperate script path, multisig( a schnorr based signature that allows multiple keys to produce a single aggregated public key and signature) is quite more efficient.
Yes you have it right. Now the reason for using a single script and not using same key more than once is for security purposes.
Using a single script is more efficient(reduces the size of the transaction since only one public key is needed) ,secured( improves privacy since specific private keys used is not shown) and not to mention simpler (since you using an aggregated script rather than multiple script).
Anyone knows about this? If my question does not make sense, please let me know!
It does.
