That one had me for a while too but I think he means this.
If its midi data, he wants that to remain intact but the sequencer to be counting off bars and the click etc twice as fast. The same applies for audio I guess too. Nothing changes in the audio but the sequencer underneath is counting off bars and beats twice as fast. (Assuming either the mid or audio is in time with the sequencer that is)
eg in the original post the tempo was 64 BPM. But he now wants either midi or audio to remain the same but the sequencer is counting off now at 128 BPM.
Musically nothing changes but the way the sequencer is counting doubles or speeds up, in fact he wants the sequencer to be thinking three times as fast.