Somewhat belated report, 48 er, about 60 hours after the temporary block. I'll keep it short: The situation is still improved, but Mack the Knife is slowly but surely making his way back. Looks like the useful window of relief from one of these temporary blocks is between 40 and 48 hours, but during that window it's very good.
So I suppose now, we go look into a more permanent block, now that we know it'll help.
To wrap up other medical status from today, the fissure in my foot is healing well (this time) but isn't there yet, the little toe appears to be doing very well, and the Dreaded Creeping Nether Lurgi seems to have had its last gasp last night and this morning. Tomorrow I need to call my doctor about renewing the referral to the podistrist, and call the orthopedist about my knees since the long-term benefit of the steroid shot has been precisely nil. (In fact, even the short-term benefit lasted, like this temporary block, about 48 hours.)