In the recent past, it was not uncommon for PhDs who got an offer as Assistant Professor somewhere to also get interesting post-doc positions offers from other institutions. When possible, they would take both positions, do the post doc and postpone the beginning of the assistant professor position for a year or two. In a steady state, this does not matter much for the stock of offers at any point in time; I don't know the actual figures of these situations (e.g. some prestige post-doc positions are actually meant only for PhDs that have an AP position so are not concerned by this trade off). Now, given the extremely difficult circumstances and the drop in the number of available positions on the market this year, one might be willing to keep the number of "double-takes" as low as possible. This would come at a cost for the PhDs who are susceptible to get this kind of opportunity and for the Universities recruiting post-docs who will have a reduced choice, but would overall increase the odds for new PhDs to get a job (post doc or AP) this year. So I guess my question is: is this worth thinking about?