Using pre-cuts for sections of long source clips are a good way to use the Replace method. If all the clips are the same duration you won't have any trouble matching up things like motion keyframes, but when the durations are different you'll have to manually make the appropriate adjustments.
I've found that some effects are anchored to the start of the clip and play out at a fixed pace, while others get automatically sped up to fit the new duration. Still other effects seem to be anchored to the end of the clip which can throw off the timing in unexpected ways when applied to a clip of a different length.
Basically how much work you save will depend on the specific edits you've made. Sometimes, Replace works great for most items and you might only need to reset one set of keyframes, while other times it might quicker to start over than to try and recalibrate all the disjointed attributes.