The last time I used fresh 34/70 I sprinkled 2 pkgs on the surface of the wort at 71* & after 30 minutes gave it 60 seconds of O2, it was down to ~60* by then. 4 1/2 hours later I had <2 second bubbles through the airlock. That was last July, yesterday I pitched some of the 7th generation from those 2 sachets in a partigyle Schwartzbier & had <2 second bubbles in an hour and a half. This morning it's chugging along with 2 second bubbles at 53*. I don't recall ever having any significantly long lag times with 34/70 but I haven't gone back and checked every time I've used it. TIFWIW