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Does a clustered index in a foreign key column increase connection efficiency and is not clustered?

In many places, it is recommended that clustered indexes be better used when used to select a range of rows using the BETWEEN operator. When I choose to join over a foreign key field so that this clustered index is used, I think that clustering should also help, because the range of rows is selected even if they all have the same cluster key value and BETWEEN is not used.

Given that I only care about what you select with join and nothing else, am I mistaken in my assumptions?

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A discussion of this type of problem in the absolute is not very helpful.

It is always in each case!

Essentially, access using a clustered index saves one indirect period.

Assuming that the key used in the JOIN refers to the clustered index, in one read [it does not matter whether it is an index search or a scan or partial scan], you get the whole row (record).

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