DF: DBT difference between rural and urban area

[Francesco661]

If I consider the default .gh file uploaded by @chris and used with DF Legacy 0.0.03, I obtain a certain difference between rural and urban site on the average monthly hour Dry Bulb Temperature (DBT) data:

If I try to reduce the urban building geometry (site coverage 0.01), set to 0 the antropogenic sensible heat and set the vegetation coverage of the rural area equal to that of urban area, I obtain this:

The difference in terms of DBT is more than 0.5 in the left part of the graph (avrMonthlyPerHour) and there is no particular evidence of the difference with the previous case. Could you explain why?

[Francesco661]

Another issue:
If I use two same Bld programmes and a building ratios of 50% and 50% I obtain the following urban DBT profile:

If I use one BLD programe (same as above) with building ratio, clearly equal to 1 I obtain another urban DBT profile:

Why is this happening?
Last consideration: if I want to use, for example, the Colibrì feature, to automatically provide the results on a series of city profiles, it might be useful to add a control on the building ratio because if it’s equal to zero the UWG component doesn’t work: