Chicago was/is a band that exemplifies a horn section, rather than horn soloists, and Lee fits that role perfectly. Saw them twice in the early days, once at a club with maybe 40 people in the audience and a little later in a 3,000-seat hall. They were a BAND, not a bunch of individuals. Personally believe Pankow was the most talented horn player in the section, but it was the unified section that mattered. Also, if you didn't see them in their early days you really can't appreciate how tight the rhythm sections was. Cetera was a highly underated bassist (until he became a balladeer), and Kath was always a monster as well.
Saw them a few years later and was disappointed, as the drugs/alcohol issues were blatant, especially amongst the horn section.