Well someone certainly is at Spurs. There starting 11 last season cost less than 100 million and was a lot better than Most sides with much more expensive sides. I know they've had some poor buys, but they have spent incredibly well.
He might make as many bad deals, but certainly makes a lot more good ones than most.
They buy a lot of cheap players in the 5-15m range and after years of underperforming (Walker, Rose, Dembele), some have started to deliver under a very good manager.
They also had the likes of Lamela (£30m), Janssen (£25m), Son (£25m) and Sissokho (£30m) on the bench. The fact that the starting XI was cheap only highlights how all their big money signings do awfully.