...It's a simple, trivial check to perform once one gets to the job site....
...It won't slow down pathfinding.
Simple, but take a look at the structures in DFHack to understand how tiles are stored.
It
will slow down pathing. Noticeably. DF uses many vectors, many long memory calls. As explained, this dramatically increases the number of memory fetches, which makes your CPU cache useless. So much so that you may as well use Java instead of C++.
I don't see why we should go through the extra-tedious and boring job of manually designating the order of tile removal, when determining that kind of order is something computers are actually very good at. I'd rather have Toady automatize it than code yet another UI feature for this.
Technical reasons.
It's easier to implement for Toady, it is one stone that kills many birds, and it is has near-zero performance impact.
That's why.
The basic idea would be to use a flood-fill algorithm every time a channel or floor removal is designated, to identify the whole contiguous region of tiles to remove. Then, treat the connected region as a graph where each tile has 0 to 8 neighbours, and apply an algorithm to turn that into a tree....
...Performance-wise, the worst that could happen is a slight slowdown when designating if you designate half the map for channeling, but it shouldn't otherwise affect your fps.
Are you kidding?
How it can help? It is normal to have multiple tiles removed simultaneously.
True, but avoiding that would require a great deal of code.
My suggestion helps because it gives you some micro-management control over the order the tiles are removed by limiting access.
Yes, more tedious micro-management, but more importantly, it takes minimal effort to implement, has no performance impact, and solves other problems with dwarfs going where you don't want them going.
Not that any of that matters.
The suggestions board is just to let us placate ourselves. Toady almost never reads them anyways.
Cheers.