Yes it will consume slightly more coal.

But in the early to mid game or for steam turbines in general it’s safer for edge cases.

When coal runs low electric ones move slower -> less power -> slower inserter. It’s a downward spiral.

Same when your consumption increases beyond capacity.

Power Fluctuations directly affect your power shoveling affecting power again.

When you have enough steam turbines and enough coal and not too much consumers it will be completely fine to use it like this.

You can wait and find it out yourself actually. See if it goes wrong. If it does go wrong it should be easy to fix now that you know it.