This is what I had expected, we did not expect to pull any this year, but thought it would lie dormant for some time while roots got established then with all the fresh compost it was planted in, it would suddenly take off, this is what happened the last time we chopped a lump off main plant and replanted, using the same compost around 2 to 3 years ago, so was expecting same result, last time it was put in a planter a raised bed, which was a magnet for weeds, the idea was once the rhubarb started the grow it would stop weeds and make the planter look better for selling house without the need for loads of work weeding, and it worked, not really what planter designed for, but it stopped the weeds.
So I had expected the same with this house, it was intended to be one plant, I carried it from main house in a dust bin, and when I took it out found one large lump and one very small lump, so thought may as well plant them apart from each other, and did really expect the small lump to fail, it was very small size of a new potato with one stalk, the other lump was 10 times the size, with maybe 8 stalks, and in both cases the existing stalks died off, and a new stalk on small, and stalks about 4 on large grew and I just watered with watering can every day unless it rained.
The small one has been eaten by some thing so not a full leaf, but it still has a single stalk and leaf, but the larger one does not look very well at all, the one stalk left is very limp and it seems to be dyeing off, I did not think you could kill rhubarb, it has always seemed such a strong plant, so wonder what I am doing wrong.