Well, that definitely explains why I tried over 100 times to get over 8,000 and couldn't. A lot of the flag/fuel rods I've been getting are 100-150 pts in the beginning rounds, and 50-60 points in the latter rounds (10-20 pts in the last rounds). Did some preliminary tests after I read this, and based on what I've observed, the score for the fuel rods is: you get TimeLeft X 10 X Multiplier, where the multiplier is 2X for retrieval while slow and 1X for retrieval while fast.
However, it also gets to the point where if you are not keeping the fire button down the entire time, there is not enough time to get to the next flag ... the timer drops *that* fast.
I'll have to try the "slow" approach and see if that fares me any better.
Thanks for the heads' up!