I thought (from discussions on here) that others believed we'd...

I thought (from discussions on here) that others believed we'd seen lower barge loadings around more like 5,400t, or even less estimated. In which case, if your numbers are to be believed, a bit of an adjustment upwards from those lower levels would be very possible. Though your numbers do seem inconsistent with what others were suggesting before and I've not attempted to run any longer-term numbers myself.

I am wary of rationalising what one wants to believe. Nevertheless, barge tonnage is obviously a factor. And you might presume heavier barge loadings over fewer trips would be more efficient.

To offset a drop to 8.6 from 9.4 average barge movements (last week to this week), you'd need to bump an average 2400t/barge up to 2630t. Which seems eminently feasible. So that could easily explain why we're seeing good ship loading figures from Arrow with slightly lower barge movement numbers.