According to the Logjam paper, the 1024-bit individual logarithm would cost around 30 (parallelizable) core-days once the group precomputation is over with. Unl

According to the Logjam paper, the 1024-bit individual logarithm would cost around 30 (parallelizable) core-days once the group precomputation is over with. Unless they're being exceedingly stingy with their hardware, 30 core-days (less than a day in a single powerful workstation) would already be 'file a ticket' levels of easy. (Note that the time reported in this newer paper is calendar time---it's still 10 core-days, so quite comparable to the non-special variant.)