Tricyrtis are herbaceous perennials. I am not aware of any species, varieties or cultivars that do not go dormant in winter, when grown outdoors in a temperate climate, including the one mentioned above, which is a yellow foliaged sport of Tricyrtis formosana.
When there is an extended warm spell during winter, some may begin to produce new foliage, but when freezing temperatures return, that foliage will die, unless the plant(s) are removed to a greenhouse.
Rb

I agree with RB - these are almost always totally herbaceous, even in our rather mild climate. There may be some very insignificant sprouting in very mild winters, but nothing that I would consider more than a pretty complete dieback. I carry a good many different varieties of toadies at the nursery and none held over have ever retained top growth in winter, nor have any of my own garden plants.

Thane, if your new purchase is currently showing top growth, I'd surmise it was grown under glass with heat (for the show), as typical plants will still be in full dormancy at this time of year, and I'd be reluctant to plant it outside now with cold weather still very possible. Keep cool but above freezing and wait until late March or early April before planting. You should be safe then.

Thank you for the answers. I guess when they say:

"Compared to Tricyrtis formosana `Gates of Heaven`, an unpatented plant, our new cultivar is more vigorous and does not die back or bum at the edges."

...they mean it doesn't die back until the end of the season. That makes sense.

I grow Tricyrtis formosana 'Gates of Heaven', a phenotype similar to 'Gilty Pleasure' and it does not die back or burn at the edges, as stated in the patent of 'Gilty Pleasure'. Environmental conditions are much different in this location, from those in Canby, Oregon and must be considerd when evaluating a plant's performance. Since the genotype of both cultivars are the same or similar, I would expect 'Gilty Pleasure' to also perform well here. I do not grow 'Gilty Pleasure', one yellow-foliaged T. formosana is enough for me and as I have been known to asexually propagate Tricyris by division, stem and root cuttings, I do not purchase patented plants.
Rb