I never said that. In 46 years of studying astrology, with the exception of 2 or 3 years when I experimented with using only the Chaldean planets, I have always used the outers. They add depth and detail.
I do give rulership to the old rulers, except when I think the chart asks for the modern planet to take the rulership.
Example of this, from a chart I looked at recently:
Saturn is lord of the horoscope with Capricorn rising and he is closely conjunct the IC. So he's powerful and I would normally give him rulership of Aquarius. But Uranus is posited in Aquarius. Therefore he holds dominion of that sign.
Saturn, clearly a powerful figure in the chart, still influences Aquarius but his influence is less direct, more "back-door". This idea, or situation will influence the way I interpret the chart.