Lenses made it the GDR had several quality ratings. Most of (all?) the lenses destined for export were first quality example, having a triangle or a Q symbol with a 1 inside. There were at least two other grades.
How the grading was determined and what it means in practice, I don't know (all the lenses I've had being "1"s).
Anyway, if the Tessar is still stiff after a relube, it might have received a knock.
The Tessar was also the entry-level lens (for CZJ) and tended to be less well built than some others, though different generations varied (later ones tending to be worse).
well, the outer trim ring, the CZJena one, has the Q with a 1. It is an automatic type lens, albiet one that you have to cock first.
I took it out today and shot it, and it is getting better. I think what I will do is give it a week or so, and if it does not improve, I will re-lap the threads by placing some clover polishing compound into the threads and work it for a few hours. This should lap the threads right on into place.
I'm sure it has had a knock, because removal of the trim rings was a real bitch! They turned very easily right up till they got to about where a filter would live, and then hung up awfully badly. Some working about with a filter and some clover in this area cleaned it up fairly well, but of course, removed the black paint in the tight areas of the threads. That said the filter never had any issues at all threading onto the threads, so, who knows.
I'm still very pleased to have this lens. The other lens I have has a filter ring that was smashed very badly, and will never hold a filter again, less you use some push on type device. This lens also uses 49mm filters, which i'm very happy about. The other lens used 40.5 filters. 40.5 filters are not very easy to find, the only solution i found was a 40.5 to series VI adapter.