the plants' reliance upon naturally occurring fires is questionable […]the plants we see are those that were already adapted to cope with periodic fires…

Yep, that’s pretty much how I would have interpreted things too, Stales. I guess it er, boils down to the er, degree of weight accorded to the different factors at any one period – but in outline, plants have developed with particular survival and reproductive mechanisms suited to the periodic fires natural in a hot landscape; and these plants have been further favoured by selective pressures created by other components of the natural world… including the vigorous animal known as homo sapiens. ;-)