pg_dump, pg_restore, insert vs copy

Hi,

When I use pg_dump to back up the whole database and then pg_restore an
individual table,

pg_restore uses COPY. Great.

When I use pg_dump to back up an individual table and pg_restore it,
pg_restore uses INSERT.

Method 1:

pg_dump mydb -R -Fc --compress=9 > method1.dmp

pg_restore -t mytable -d mydb -R method1.dmp

I will see COPY in both OS and SQL.

Method 2:

pg_dump mydb -t mytable -R -Fc --compress=9 > method2.dmp

pg_restore -d mydb -R method2.dmp

I will see INSERT in both OS and SQL.

Is this an expected behavior?

This is a big table with million rows in a big database. How can I speed
up individual table back and restore

if this assessment is true?

My PG version is 7.3.2 (I know, I know, it'd old...)

Thanks,