Not a good analysis, IMO.
Reverse thrust is most effective at high forward speeds, so you should not try to rely on more reverse thrust as a last-ditch attempt to save a too-long/fast rollout. Also, unless you want to FOD your engines, using more than idle reverse at less than 60 KIAS or so is inadvisable.
At low speeds, idle reverse will remove any residual forward thrust, making braking and steering more effective on slippery surfaces like wet paint stripes.
OTOH, if you want to use more than idle reverse early in the landing roll, then just do it.