Wilcox became one of the most successful announcers and pitchmen in radio and he was a pioneer in making commercials part of a program's story.

The "Wistful Vista" website put it this way:Wilcox was one of the masters of the integrated commercial, a technique that was popularized on Ed Wynn's and Jack Benny's shows.

He knocked at their door as just another person in their stream of visitors, but no matter what the conversation had been about before his arrival, Wilcox somehow managed to turn it to floor wax within a few moments, and then struggled to promote his product over the continuing action around him.

In her "By-ways" column, Florence Burlingame Taylor wrote:Harlowe [sic] Wilcox was introduced as a young lad, just getting a start in radio.

[citation needed] Wilcox can be heard on a 1937 promotional film [13] for Stewart-Warner refrigerators which was preserved by the Library of Congress, and which also includes an appearance by 18-year-old Art Carney.