with better network performance of today compared to 6 years ago...

[Robert Maynard]

It would work like a VSI rocket does in reality.

Ship thrusters would have variable specific impulse with thrust inversely proportional to specific impulse. Higher specific impulses (more fuel efficient, in terms of total delta-v) would provide less thrust (lower acceleration) and lower specific impulse providing more thrust (higher acceleration). The precise slope for the relationship of specific impulse to thrust would vary between engine types, and the amount of thrust needed for a given acceleration would, of course, depend on ship mass.

Interesting - this requires some working out - to see how capable existing engines are and which ships the proposal would favour over others.