1. It's a matter of experimenting to see what works for you. You could try using the frequency multiplier, and then run without the frequency multiplier. You could also try running the frequency multiplier on OUT2 whilst running OUT1 without the multiplier. There are no hard fixed rules when it comes to experimenting with different combinations of waveforms, amplitude settings, amplitude wobbles, frequency wobbles, run time of program sets, which program sets to use, etc.
2. As far as know the source of this idea came from:
http://www.dnafrequencies.com/1999.shtml. It is worth noting that people have been using remote mode for years without using the multiplier and getting results regardless. You could try without, and if you get no results then try the multiplier. Start with your gut feeling about which is best, but remember to experiment if you don't find the results you desire.
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