Like a majority of hobbyists and gamers, we see scale as referring to a standard that is used to express a certain category of miniature. Here's how we look at it:
Using the above numbers, an alien that is released for use with 15mm scale figures might measure 20mm or even 25mm tall in actual height. Does that make it a 20mm figure? A 25mm figure? Some might say "Yes"...Mad Robot says..."NO". That figure was sculpted and planned to be used in conjunction with the figures currently available for the 15mm scale category. In this sense, the word "scale" becomes a category of models, not a reference to the actual height.
The same kind of logic applies to 28mm. Within the category of 28mm, there are heights of 28mm, 30mm, 32mm, even 34mm. Add to that the wonderful world of proportions! Is there a difference between 28mm and 28mm Heroic? Most certainly. But fore the sake of continuity, for the sake of avoiding confusion, they all get lumped in to the category of 28mm gaming.
Is there anything wrong with this? Well, Mad Robot says..."NO". As long as a manufacturer can effectively demonstrate how their models compare to others within the "28mm" category, we see no reason to nit pick about the exact height of each figure that is released. At Mad Robot Miniatures, we make no effort to hide how our figures stand up to others. Like every other miniatures company, we strive to put the best product we can out there for folks to purchase, paint, and enjoy.
Final words, on a personal level, from The Mad Robot himself..."There are all shapes and sizes of people in real life, both on and off the battlefield. As long as you are happy with the way a figure looks in your army, you should buy it, paint it, use it and leave it at that. These are games...have fun and enjoy them!"