It isn't that I don't think an alcohol wash before treatment would be good to do. For me, It was more of a decision of do I want to kill those 300 bees from the package when they could be helping to keep the cluster warm on those early april nights. I based my decision on the way a package of bees declines in population prior to ever having more new bees emerge. My thoughts were that OAV isn't supposed to bother the bees, so it would be better in my case to do a carpet treatment to kill off as many varroa and know i'd have healthy bees emerge from that first round of brood.
I think that if a person was in a warm area or starting their packages later than I did, it may be a good thing to do to check them. If for no other reason than to see how well the package producer was keeping their mites in check prior to shaking the bees.
Now i've questions for you. If you were put into the same situation as I. Starting packages, early april in NY. Knowing that you could get rid of most of the package mites. Would you do alcohol washes on each, a portion of them, or blanket treatment with OAV/OAD ?
Your answers to those questions should be based upon your style of management and what you feel would be best in your situation. We as beekeepers, wether hobby, sideliner, commercial, all do the same things. Try to figure out what works best for us, and repeat it.