I noticed that Bullen, Bovey, et al consistently use Auto_Open macros in their books rather than the Workbook_Open event. But I can't find any place where they discuss why.

I also notice on Bovey's AppsPro site he has a technique for trapping all events from the Workbook module and handling them instead in a custom event handling module.

So the questions.

First, why do they use Auto_Open? If it is for backward compatability with older versions of Excel, that is irrelevent for me. But if there is a valid technical reason... well, then, that may be an entirely different story.

Second, on his site Bovey alludes to possible dire consequences of putting event handling code in the workbook module but he doesn't really make the case fully. So is this a genuine concern? I'd like to decide on a standardized approach to structuring my code and I'd prefer not to add the overhead and complexity if it's not really a big concern.

Coincidentally enough, this was asked of Rob recently here.
HTH