Water softener so I have no problem lathering Trumpers, but I understand it is a "thing." I also use a shot of scent-free Aveeno gel or EMJ with all my soaps, and find it improves lathering generally, with no degradation in performance.
Funny. I have this too, the one and only time I bought a shaving product because my wife liked it (she happened to be with me in the store and like the scent best of the shaving soaps on display). I have never opened it, but, how bad could it be? Did you try soaking it in hot water first? Oh well, it can help make my bathroom closet smell nice. I don't think any other soap I've had has such a good scent unopened.I thought I could lather anything ... Williams, Mitchell's, Truefitt, Taylor, all the ones people had complained about, no problem. I'm the Lather King, been doing this for decades, the Master!
Then I got a hold of a beautiful bowl of Trumper's sandalwood. A lovely scent and presentation but whoa, disappearing into nothingness lather ... crap, ugh. What the ... ?
I've saved it since 2010 or so, thinking it will someday work and I'll get the magical water/soap ratio right, maybe some super badger brush, rain water from heaven, stars aligned. But no. What a waste.
Just sniffed it a few minutes ago ... love the scent. Maybe I'll try it again tomorrow. Maybe.
With my just-purchased puck of Trumper Limes, it doesn't matter what I do -- Load the brush more, try more water, less water, spend more time building it up...I end up with a thin, disappearing lather. (I bowl lather but then do a partial face lather before brushing on additional lather from the bowl) We're talking before I finish the right side of my face, the left side has virtually evaporated and I can clearly see my skin through a thin film. I have to keep re-applying mid-pass.
Why can't I get a good lather from the Tumper hard soap?
P.S. I LOVE the trumper creams!