As an exercise in both parameterized architecture and architectural
rules, the class photographed and measured various stair cases, and
gave a qualitative judgement of the feel of the stairs. While most
people were happy with "standard stairs" (stairs whose rise and run
meet certain standards), a suprising number of people were fine with
some sets of stairs that fell way out of this range.
As a common set for the class to compare, everyone gave a qualitative feel for the stairs outside Needles Hall to assess whether or not they were uncomfortable on those stairs. The vote was 7 were fine with them, 8 were uncomfortable (plus two instructor votes for "uncomfortable"). These stairs have 6.5" rise and a 11.5" run. The rise times run is 74.7, while the rise plus run is 18. The standards given in Dietz suggest the rise is a bit low, although reasonable; the rise times run is okay; and the rise plus the run is a bit too large.
As a second common set for the class to compare, everyone is to give a qualitative feel for the stairs inside the Davis Centre. These stairs match Dietz's criteria, with a 7.5" rise, a 10" run. The vote was unanimous: everyone felt these stairs were comfortable (although one student said they were uncomfortable when taken two-at-a-time).
The point is: when stairs are made to the common guidelines, everyone finds them comfortable. When built outside the guidelines, a reasonable fraction of people will find them uncomfortable.
Disclaimer: everyone in the group goes up and down the Davis Centre stairs multiple times per day. Thus, the evaluation may be biased based on "what we're used to".
In the table below are links to the stairs that each student (and one instructor) measured and photographed. Click on a picture to get their report.