struct tty_driver

Ted, I wondered:

Looking at 2.5.60 I see

struct tty_struct {
	int     magic;
	struct tty_driver driver;
...

and it looks like this struct tty_driver is never modified.
Since it is rather large, why not replace it by
	struct tty_driver *driver;
?

As it is now, the initialization in init_dev() does
	tty->driver = *driver;
just duplicating constant data.

Is this a historical relict, or does this duplication have a function?

Andries