In a video on the Tuscarora Lodge website a winter trail is mentioned. It bypasses the established portages from Brant to Gillis. Has anyone taken this winter trail?

Yes, at least part of it. I was up there in mid January camped on Brant, and trying work my way up to Blue Snow. While camped on the south west bay of Brant I learned that Bear P. and his crew were camped on Crag for the month. They set an excellent, flat trail from that south west arm of Brant along the creek that flows out of Brant to Crag. I snowshoed that trail over to Crag to visit one afternoon, but started getting cold at dark so turned around and went back to my camp. I was not sure if they set a trail from Crag to Gillis or not but would not be surprised - it was not far and that crew are fine trail blazers, though I believe there is some elevation drop from Crag to Gillis.

They all pulled out at the end of January, so no idea what the trail might look like now. There's been a lot of wind, snow, and melt since then.

Yes I was there in Early January with Bear and his sister. I skied in Pulling a sled to Crag. I brought in Fresh Veggies and fruit and stayed with them in their winter tent. We took a day trip from Crag to Gillis and down to Mora and back. I needed to be back so I skied out the next day. The bushwack trail between Crag and Gillis we nicknamed the Billy Goat trail. It was set before I arrived, but we walked to the ridge from camp then skied across a semi open forest until getting to the Plunge down to Gillis. Awesome icicles on the cedars on Gillies.
Was on Partridge last weekend. they have had considerable snow since then, it will be busting trail for sure now. You may be able to follow a slight depression in the woods section but wind will have erased all open areas from Brant to Crag for sure.

Thank you both.

I'm heading out of Round next week. Plan right now is to shoot for Bat by way of Brant. As always final route/destination decisions will be determined by the conditions.