An option whether to rerun all previous steps would save time when nothing has changed from previous steps. Currently, if queries become complicated with multiple sources, it can take up to 5 minutes for preview to refresh before allowing further edits in Query Editor. Since none of the previous steps changed, this slows work down immensely. Posted as an Need Help issue originally: https://community.powerbi.com/t5/Desktop/Query-Editor-preview-reloads-all-previous-steps-after-an-edit/m-p/386878#M176159