If this was wlp001 and you were going for a bigger beer, say a double IPA, then I'd say "do it". Since this is a saison yeast, you should cut that cake and take about a 1/2 of cup of that slurry to make your next saison. Remember, the yeast is what's making the flavor here and you want it to go to work for you. If you keep the fermenting temperatures warm attenuation should not be a problem. Good luck!