Optimizing sequential scan in PostgreSQL

Question

PostgreSQL 9.4

In the article about hardware optimization for PostgreSQL server was shown that too much moving disk head may cause performance bottleneck. As far as I got, for the sequential scan, it'd be much faster if the cylinders with blocks of the same table are located as close as possible. So, if we're inserting data into a table, the data will be placed in "sequential order" on a disk-storage, therefore reducing the disk head moving overhead.

But I presume that such location may be break in time. Is there a way for postgreSQL to maintain such "clustering" (if I can say so)?