Re: When and how to switch from SS to Crossfit?
I suppose it depends on your goals, and your current level of strength.
If you've done two SS cycles already, why not dive into WODs full-time now, scaling where necessary. Many people have great success with scaled WODs, even without any lifting background to build a minimal strength base.
Once you've been at WODs regularly for a couple of months, you'll know whether you need more strength right away, or whether your goals are being realized with your current starting point. WODs by themselves will make most of us stronger - especially newbies - especially if you do the CFWU.
I did SS before jumping into WODs, and got to the "novice" level on coach Rip's charts. It helped a lot, leaving me strong enough that I could do most metcon WODs as metcon rather than as strength workouts, and didn't need to scale the majority of the WODs.
But still had to scale some of them - which ticked me off more over the months. 8 months of WODs later, my overhead strength was the primary reason I was still getting a brutal Fran time. Linda was right out as Rx'd, because my bench was garbage.
So I'm a few weeks into another SS cycle, to shore up those weaknesses. I'm scheduled to return to WODs in mid-late March, though I'm missing them now pretty fiercely.