I don't really agree.
It's easy to blame the board but it's not a straightforward situation really. It's fair to say that the idea of sacking Koeman just 9 games into the league season would not have seemed even remotely likely just 2 months before it happened. Unfortunately things went very bad very quickly, and the European games meant that while the period of time was short, the number of games in the bad run was actually pretty large. With this in mind, it's not exactly surprising that the board didn't have a ready made replacement lined up. It's also worth noting that he managerial market is one that changes constantly, so your contingency plan hinges on what other clubs do and what decisions other managers make.
I said yesterday, if we fail to get Silva then this situation starts to look a bit farcical, but if we do get him, what exactly has gone wrong? It was clear from day one that Unsworth would be in charge until the international break, and if we bring in Moshiri's first choice during that break, it would seem like a job well done in all fairness.