Depending on what type of tool you are using and your soil type and moisture level when working the ground, there may still be an open shank slot beneath the soil surface in the spring even thought the FC has made the surface look uniform.

To minimize the effects of this open air pocket on the crop planted above, I think it is best to do any "deep tillage" at a pretty steep angle to the future rows. We have some customers who "deep rip" in the fall then run our Dawn Pluribus strip till units over the top in the spring. If you are going to rip like this I suggest running the ripper at a significant (maybe 30 degrees?) angle to the spring rows. Trying to line up say a 12, 16 or 24 row strip till bar over multiple passes of a say 4, 5  or 6 shank ripper is just not in the cards.

What folks are in fact finding is that even if they believe ripping pays, they do not need to do it in every field every year. If you want to "deep place" P or K with a ripper do it once every couple years. In other years just run the strip till bar with your N and maybe some P and little K in the spring.

Angled deep tillage minimizes possible negative effects on the following crop that occur if a row happens to be lined up over a subsurface still open slot. This year in some areas crop directly over a deep tilled slot seemed to suffer more in drought than crop planted into soil with good structure. jmho.

Jim at Dawn