I also found this irritating. And at first I completely eliminated block 0 (by using an offset), but later found that having a block 0 that cannot be used for load is the traditional way, so I changed Gforth to follow that way. Blocks are a traditional thing. If using Block 0 for something else was good enough in the times of floppy disks, it should be good enough now. In any case, it seems to me that you have understood the issue, and have no need for clarification, so I am closing this ...
