The last line of ToolHelper.isToolEffectiveAgainst uses the vanilla ItemStack#func_150997_a method to get the tool's break speed for the block, but it should probably use the Forge-provided Item#getDigSpeed method instead since this is used for the actual break speed calculations when breaking blocks.
The last line of
ToolHelper.isToolEffectiveAgainst
uses the vanillaItemStack#func_150997_a
method to get the tool's break speed for the block, but it should probably use the Forge-providedItem#getDigSpeed
method instead since this is used for the actual break speed calculations when breaking blocks.