It works in the 1st Pokemon Red? Let me see if I really got it. By killing a poke that got his main status, f.e. SPC. atk I'll get one EV for SPC. atk and by acumulating 4 of them when I lvl up I'll earn a bonus point?
Sort of but not the same as it is in gen four it gives you evs equal to the stats of the pokemon you face so mew would give you 100 in each stats evs maxed out for one stats at 65535. I got this information from http://bulbapedia.bulbagarden.net/wiki/Effort_values