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My past experience of multiple transistor 'darlington' configurations in big PSUs is not good. Under short circuit, there is a risk (especially with slow op-amps) of excessive current causing failure of one of the drivers, BC337 & 2SC1173 in this design, which results in unregulated voltage and current flowing to the load.
I would have some concern that the combined base currents of six 2N3055 transistors while running at around 6A each would be close to, or exceeding the 3A maximum rating of the 2SC1173 too.