What does this mean? (v39 test on decreasing Raid defense team buff)

[Petri]

Hello, we have now started this test. You can read more information about the test here:

Version 39 Release Notes & Status

As described in the Release Notes above, we have now started testing how decreasing the raid defense team buff for high-level Raids affects the gameplay experience and defense win rates. There has always been a buff for all heroes in defense teams in raids. The buff is percentage based so with hero powers growing the difference between the power of the same hero in attack and defense has become wider. In the test, we are slightly reducing the buff for most legendary Heroes in the game. The high…