Really enjoyed this. Did the 3-4 method -- this one was conditioned for about 31 days, refrigerated for about 6. Poured a solid black with a tan foamy head. Hints of chocolate, barley, a little dark fruit/raisin. I usually use slightly less table sugar than Mr. Beer recommends when bottling, and yet this still came out a little too carbonated for an irish stout. Next time, I'll try using even less sugar. Otherwise, this is very similar to the Winter Dark Ale, so in other words - excellent! Just brewed the Bewitched Amber Ale last night & thinking for next month of upgrading the Centennial Zest Ale recipe I came up with (see signature below) with using 2 oz. of Centennial Hops as opposed to one and Safale US 05 yeast instead of what normally comes with the Mr. Beer refills.
Very few brewers now use secondary fermentation. There are reasons to use it but only for more advanced beers with additions which are done in a secondary or for extended bulk conditioning.
As Jim said, the items that we are concerned about can't fall up. Also the LBK protects the beer from oxidation because of the layer of CO2.
It would seem to me that after the Krausen it may be less likely than during. Reason being many people siphon to a second fermenter which not only is an open container no matter how well you transfer you are adding oxygen. Not denying what you said just trying to wrap my head around the process.