This is actually one of the more amusing statements I've seen lately, especially as I have crimped LOTS of 4/0 lugs... What factual basis do you have for this statement?
The information was given to me by one of our neighbors who, with 40+ years in the industry, is the chief electrical engineer for one of the largest electrical wire and equipment distributors in the US. His comment was in answer to my question as to which "crimper" I should use when I was installing my own windlass. Unless I was willing to spend several hundred dollars for a tool for which I would only have very limited use, he indicated that the less costly devices sold by Lowes, Home-Depot et al, simply made poor connections. By comparison, the "Swage-It" tool is inexpensive, has many applications, can be used with relative ease in the narrow and tight confines of a boat; and, by applying uniform compressive pressure to the throats of the lugs ensures that the material of the lugs "flows" in and around the stands of the copper wire providing the best connection--just as does a swaged fitting on rigging wire.
Frankly, I don't care one way or another, nor am I an expert on the subject. However, I did, in 2006, go through the process the OP is going through, and thought he might benefit by my experience. Or not.