Certain Actions Take No Extra Energy in TTD. Balanced?

[Smallie Biggs]

The game says that "attacks drain [energy] faster" while in TTD, but sneak attacks (using the "E" prompt), minelaying, and grenade throwing do not consume extra energy in TTD. I'm not sure if this is a bug because this quirk seems difficult to miss, but for balance reasons I think this should be revisited by the devs. Furthermore, people use the 

Spoiler

patient step

armor to use a lot of mines and sneak attacks in TTD. Feels overpowered. Yes I know I don't have to use it, but I'd like to have it in the game but in a more balanced way.

Do you think that sneak attacks, mines, and grenades should cost energy during TTD like other attacks, or should things stay the same?

PC 1.0.6.0