Both cities are the core of metropolitan areas; Lyons is close to 2,1 millions, Pittsburgh nears 2,3. Both territories are complex, beginning with their definition. But for remote islands, metro areas are never easy to define, and most of the time you are in fuzzy territory. Some things can somehow be measured, like functional relations, but this is not necessarily, what gives you a coherent territory. So defining the limits to your plans is quite an art, sometimes, as politics also count.
Regional plans are an interesting instrument; they address many things people care about in their everyday life, as large-scale landscape quality, transportation or efficient infrastructure. But in some countries, due to the lack of a separate planner professional career there is a confusion with urban planning and design; regional planning does not deal with architecture or building heights, but for some cases in which the issue appears through landscape quality regulations, as when dealing with skyscrapers (an even there, often in a tangential way).
Lyons is quite French, in the sense these 2,1 millions are distributed in 514 Communes according to the metro statistical definition of 2009. As this is a territory surrounded by mountains and rivers, and some parts have deeper links with the core than others (the will to enter a club also counts…), in the end you have a complex shape when you define a regional planning scope.
So the SCOT (Schema de Coherence Territoriale) 2030 Agglomeration Lyonnaise covers just a part of that large area. Just 73 communes, which house 1,32 million and most of the jobs on 730 sq km.
When it comes to regulate physical things like architecture, there is the Plan Local d’Urbanisme of the Communauté Urbaine de Lyon (just 58 Communes, that have agreed to use a common format for their planning instrument… in that sense, French planning is a bit like a set of Russian dolls, scaling up or down…). 8 of these communes are in fact wards of Lyons proper (some 400.000 on 47 sq km).
The limits of metro Pittsburgh (metropolitan statistical area) covers 7 Pennsylvania counties. But the South-western Pennsylvania Commission, which manages the regional plan, covers 10 counties, with an overall population of 2,57 million on a 18.432 sq km area. Just in order to compare, Allegheny county, in which Pittsburgh is, is 1,22 millions, on 1.929 sq km. So, yes, it is less dense than Lyons (small surprise in that).
Pittsburgh itself is some 300.000 in population on 151 sq km. PlanPGH is Pittsburgh’s Comprehensive Plan, now in process. There is where architecture happens…