The main idea is to avoid working with recorded wav synth sounds and to be able to change anything until the end of the song. u can work entire songs with just one patch synth with polyphony of 5 (depends)
If u work on a midi part and find something that u like maybe u would record it so to be able to program another sound. U must keep the midi file which at any time must represent the wav u have recorded. You must organize the names (same for midi part - patch sound name-wav file). So at any time when u want to change something u can always delete the wav files reopen the patch for the specific sound and make the correction. With that type of work u can even finish entire songs that they 'll be in midi so u can even master it on any resolution! (96 32bit). So let's say that u have a sampler and a powerfull synth- It's all that u want.
Fix it until it makes u smile-