It's nice to finally come across someone putting words on what you think you've been hearing. Ben Ratliff helps me out:

Aside from any personal language of harmony or rhythm, the overriding qualities of aggression and restraint are what have built post-bop saxophonists into major figures. Those that zealously explode (John Coltrane, Eric Dolphy) or forlornly implode (Wayne Shorter, Lee Konitz) create cults.
(emphasis mine)

and later

Mr. Alexander, by contrast, played on the beat. He used some of the same improvising patterns as Mr. Coleman, and a broad sound that stuck more often to the lower-middle register, which he occasionally escaped for unexpected effects like a fluttering figure that became a rough overtone shriek, as if a bit of Coltrane's wilder late period had been smuggled into more formal music.
(emphasis still mine)

I hear that all the time. Take Jacques Schwartz-Bart, who, at his best, fits both the Wayne Shorter forlorn implosion and Coltrane smuggling bills. For anybody, really, who is interested mainly in 60s style bop, but also a bit by free jazz, that use of overtones is part of the lingua franca. Which makes it slightly boring, which is why players who navigate the in/out line more subtly like Ellery Eskelin, for example, are more interesting and advanced, to me.