My apologies in advance for the length of this post …
I’ve been learning (and continue to do so) to create models with smaller file sizes. Because I’ve developed an addiction to SU (lol), I tend to scrutinize everything, and wonder, “can I create that in SU?” Recently, I downloaded a model and immediately noticed that Model Info indicated there were no Edges and no Faces. It suddenly occured to me that, no matter how annoying it was trying to break down that model, the lack of Edges and Faces in Model Info was directly related to the fact the whole model was a collection of components, and somehow, even though Faces and Edges DO exist, the file size comes out smaller. I know it sounds like I’m rambling…but hang with me.
Today, I made a simple model - vertical blinds with valance for a sliding door. I wanted to compare file sizes. So I made 5 sets of blinds, each with the exact same measurements, each built in the same manner:
a. One was saved ungrouped.
b. One was saved with all parts grouped as one.
c. One was saved with each part having been made an individual group.
d. One was saved with each part made into a group, then all the individual groups, grouped together.
e. One was saved with each part made into a component, then all the individual components grouped together as a component.
Of course I immediately noted the vast difference in file sizes between “b.” and “e.,” and “c.” and “e.”
The models were created in SU8. I then opened “e.” in SU2014 (Make). In looking at Model Info, there was a difference in Component Instances and Component Definitions.
a. In SU8 there were 3 Component Definitions. In SU2014 there were 4. What are Component Definitions, and why do those two stats differ?
b. It appears obvious that there is a connection between the Instances and the Definitions. A manual count of the components numbers 33 - that is counting each individual component (32), and then the nest of components as 1…equalling 33 Component Instances. But in SU2014, the number of Component Instances is 34. Why would the Instances differ between the two versions of SU? Am I misinterpreting how the term “instances” is used in SU?
BTW… I searched “component definitions,” but it seems of the MANY threads on the topic, the discussions are all technical stuff- changing this, editing that, tweaking, contorting and other such stuff. I’m just curious about the seemingly contradictory stats. Maybe a slight case of OCD. 
