Via the investigative findings of top players Dense, Baiqi, and stupid:

When attached to a single miner, Gauss correctly consumes resources in accordance with the "efficiency" of the resource type being mined.

However, if Gauss is attached to multiple miners (and/or miners with multiple resource types being mined), the resource consumption is incorrectly applied.

The loop that determines the number of resources to be drawn from each miner (given the resource types' efficiencies) will yet reduce the Gauss' remaining resources needed by only the actual quantity of resources decremented from the miner (without the efficiency multiplier for non-scalar types), leaving more resource consumption remaining than it should for the next miner.

If, for instance, you have a Gauss with resource consumption stat of 29 connected to three miners, and the first miner to be drawn from contains tensor, the second contains infiar, and the third scalar: to charge once, the Gauss will use up not just the 17 tensor that should be required (17 x 1.75 > 29), but also 6 infiar (29-17=12, infiar efficiency is 2 and 12/2=6), and also 6 scalar (29-17-6=6, scalar efficiency is 1 and 6/1=6). So even though the total efficiency value of all those resources should have been 47, it was only applied as 29 for the shot charge, and meanwhile 6 infiar and 6 scalar were wasted.

Note that: in the case where scalar is the first priority miner to draw from, and contains enough resources to satisfy the consumption requirement, this bug will not be apparent (as an increased efficiency multiplier isn't coming into play at that point).