I think the lack of detail may be because different growing conditions produce different results for the same cultivar. A strong scape when grown in sun and a floppy scape if grown in shade, e.g. Weather, light, wind all affect a plant when it wakes up from dormancy and how it grows. With the erratic conditions that are often served up during a growing season in my location, there are not many plants that don't behave differently in different years depending on what they were served that year. That even includes native plants. It would be really hard to plug in a characteristic and say with certainty that is how a plant will perform.
