The summary clearly states inTERbreeding, the title turned it into inbreeding which is more or less the opposite. But this is Slashdot where the editors can't write and the posters can't read.
except that TFA includes the quoted title from the summary...
It implies that one is going from say Windows to OS X repeatedly.
For me, with some overlapping such as windows when provided by employers, I went DOS - OS/2 - Windows - Linux - OS X.