Holy crap, @MoiraGoggin, that actually appeared to work! I did consider that originally but really didn't expect it to merge all the BOM's as well. But I just did a test on my local 4.5.4 system. I created 2 separate items, and then created the applicable BOM's. Then I created a MERGE item, and merged each of those 2 items into it. Note: The I/M Item DRM Utility performance was apparently fixed in 4.5 (PU3) and 4.40 (PU9 I believe).
Fyi, I noticed that the components on the new automatically-created MERGE BOM, were the components of the last item to be merged during the Utility not that it appears to matter.
Was able to then delete the MERGE BOM via B/M, and then delete the Item via DRM.