It's been a few years, but I don't think the Redfield herd path ever was connected to the old Twin Brook trail.
The Redfield herd path starts along the Left (W) bank of Uphill Brook, behind the camping area. The path follows the brook, S and then SE, towards Redfield.
The old Twin Brook trail leaves the current marked Opalescent River trail about 100 yards (I think) W of the camping area (before you get to the camping area, if you are coming from Upper Works). That trail makes SW into the notch between Cliff and Redfield, and never meets the Redfield herd path. I don't believe you will get to Cliff by starting on the Redfield herd path.
I always have trouble finding the start of the old Twin Brook trail. But you'll know it when you're on it, because it's basically a river of water and mud, with old corduroys floating in it.
The "traditional" herd path to Cliff is a right turn off the old Twin Brook trail, near the height of land in the notch. This nasty path leads to the top of the NE summit of Cliff, after which a walk along the ridge over a series of bumps, fianlly leads down into a small col, and then up the the true summit (which should have a sign).
I have also heard abou the "new" path which is being planned for Cliff, but I haven't seen any information about the status. I think maybe it's been flagged, but is not ready to use. My understanding is that this path will surmount the NE end of the Cliff ridge, avoiding the old Twin Brook morass.
I believe I have seen discussions on this site that the flagged trail has not been cleared, and that it should be avoided, becausre the flagging will lead yuou into heavy blowdown. Pete Hickey should be able to provide more detail.