For once gcle and I agree. The Berlin Treaty probably had no real effect on the course of events in the Balkans.
The continuing decay of Turkey-in-Europe invited other powers. .....Russia, Britain, Austria-Hungary....to assert the interests they saw as vital. The clash of interests would have brought these powers into conflict at some time anyway.
I would favor looking at the Berlin Treaty as a continuation of the "system" put in place by the Great Powers at Vienna in 1815. It may have acted to put off any reckoning by powers concerned with the Balkans, but as all thing do, the "system" died by August, 1914.
Edited by pikeshot1600