Summary

When holding down the mine button on a straight line of non-solid blocks that can be broken instantly, there is a delay after breaking the first block before the second block can be broken. The blocks don't have to be in a straight line, but it is easier to notice that way. This delay only occurs after breaking the first block. When the second block is broken, the rest of the blocks after it are broken immediately after each other. 

This appears to occur only in Survival mode.

Steps to Reproduce:

1. Place down a non-solid block that can be broken instantly in a straight line.
2. Switch the game mode to Survival.
3. Hold down the mine button on the blocks.

Observed Results:

After the first block is broken, there is a delay before the second block can be broken.

Expected Results:

The second block can be broken immediately after breaking the first.