\setupbackend[export=yes]

\starttext

    nop: [one]\kern 10pt\kern-10pt[two]\par
    nop: [one]\kern-10pt\kern 10pt[two]\par
    nop: [one]\kern 10pt\kern-20pt[two]\par
    nop: [one]\kern-20pt\kern 10pt[two]\par
    yes: [one]\kern 20pt\kern-10pt[two]\par
    yes: [one]\kern-10pt\kern 20pt[two]\par
    nop: [one]\kern-20pt[two]          \par
    yes: [one]\kern 20pt[two]          \par

\stoptext
