I recently used my yeast twice, here is what I did. I brewed and fermented a batch of beer in a plastic bucket for 14 days, everything went well. I monitored the process with my iSpindel and all was good. I kegged the 1st batch and I rebrewed the exact same recipe at the same time. I didn't clean the fermenter, I simply tranfer the wort in the fermenter with the yeast from the previous batch. The fermentation went well, I used the iSpindel to monitor it. I tasted the final beer and it tastes good. The beer I brewed is a belgian wit. Finally, my question is, what are thé possible down sides of doing this ?