Gary and I have discussed this in the past. We felt there is enough difference between the two threads to justify keeping them separate.
I note that there are currently 5 threads on the first page devoted to various offerings from GEC. I don't think two threads devoted to Case knives is excessive.,
edited to add:
On the technical side, I'm reticent to merge two threads if both have existed for a spell. When the software merges two threads, it sorts all the posts by time stamp. So any conversations which have occurred within a thread will get interspersed with non-sequitur posts from the other thread. IMO it takes away from the threads.