Should we change the return signature of sync?

[davidpaulhunt]

Do we want to automatically throw ourselves and stick with

let result;
try {
  result = whitelister.sync(rules, params);
} catch (e) {
  // handle error
}

or should we avoid the try block and let users deal with it as they please in the form of

const [err, result] = whitelister.sync(rules, params);