Well, following a curation trail (e.g. voting after a leader-vote that is typically larger than yours) is very unlikely to give you curation rewards, unless the really big hitters come after you. You should follow a trail if you support the type of content that is curated, not for curation rewards. If you want curation rewards, you should vote these posts before others. Curation trails increase the curation rewards of the account leading the trail, but usually not for those following it. Does that answer your question? If you're interested in the math behind curation rewards, see here.