i have found left/right/backwards uses little or no gas.
The trick is to stay in the room long enough to photograph all the animals. And grab all the gas and most of the film. Even just coasting which most people do, leaves unphotographed animals, some appear after a brief pause, just as your exting the room, leaving you just short of 30 thousand points.
Hover near exit with short backwards burst until sure all animals are gone
Approximatly 2000 pts a room timing wise. 3-5 backwards thrust burst.
It seems if you go backwards about a room length, a room length and a half timing wise, adding up all the short backwards thrust. Or just hold position in a safe spot. In short backwards bursts.An inch or so, about a dozen times all together.
Co-ordinate your left hand to follow safe path to get gas and film, remember to steer backwards which uses very little or no gas. A litttle tricky till you get the hang of it but it conserves an awful lot of gas. So plan your route accordingly.
What I mean by this: coast past rock/obstacle/opening, drive in reverse, minamal or no gas used.
Yes it is tricky to take pictures and steer boat backwards but hey it works for me. So drive backwards whenever possible to pick up fuel and film.
Or to get into position for whatever.
This method usually and easily nets in the high 40's and low 50's.
Hope this proves usefull.
Kings-