Yes, there's no argument that progress shouldn't be in one spot that doesn't clutter and stiffle other discussions. They are useful threads, for me at least, to see how people progress over time, and I learn a lot about how long it takes to achieve objectives and learnings from it.
The question is to how best to handle it. The options, unless I'm missing something are:
Accomplishment thread: This is more for genuine breakthroughs in achievement, and not personal strategies or goals
Superthread in general forum: hard to track individual progress, which for me, is the whole point of them
Users profiles: No easy way to see people's updates, without actively seeking it out.
Ban altogether: Stiffles a lot of conversation and engagement
Subforum: Best option for me, it solves all the above, and allows people to easily ignore if they chose to.
There are potential downsides, in that some threads are not incredibly insightful or useful, but in general, that gets managed by lack of responses or engagement. So the better threads, will last longer and rise to the top.