If you're dealing with trying to get your regular straight back into shape, then use the shavette. If you want to get that straight back into nasty sharp shape, see about sending it to Lynn, David Uthe, or any of the other honemeisters here to get it scary wicked sharp.

As for how many laps, I dunno. For me, it's a sound and feel deal. I take a razor that's a little off and begin on the boron carbide, and go with that until it just feels right. I then wipe the razor and repeat on the chromium oxide, again, sound and feel. I then wipe the razor, hit the linen for 20-30 laps, then hit the plain strop for 25-50 laps. I try to go much slower when hitting the pasted strop, mainly for the extra tactile feedback. The sound changes from a little gritty sound at the beginning to a very smooth sound at the end. It's usually somewhere in the 30-50 lap range. Make sure you're just using enough pressure to keep the edge on the strop, nothing more.