The Chateau Frontenac as it stood in 1910, and what it is today — originally designed by an American architect (Bruce Price) and added on to decades later (the central tower by Canadian William Sutherland Maxwell). Not only did they manage to quadruple the size of the hotel, they also augmented the grandeur of the building and made it even more iconic. Why the heck can't we do this now? Why do we have this reluctance to actually make history instead of being limited by what was done?
I can see why creating a historically dishonest building from scratch might confuse perception, but when it comes to additions, the rules used in creating the original building should be fair game. There really should be an option for a more seamless aesthetic, not just some watered-down ghost of a building that differs from the original. In this day and age when stone can be carved by computer-controlled machines, it could even be an expression of technological advancement.