It *could* be added, but it doesn't seem all that useful outside this very specific use-case. It would be asking for something like
/set -w %var.* 0
When you could just do
/unset %var.*
Seems very much like an edge case. Write your loop or just reset the table with { hdel tab | hmake tab 100 } (which, as mentioned, your initializing alias should already do)
