I've only done one stepped starter, and I did the crash/decant approach. It wasn't because I thought very hard about the decision, I didn't have enough space in the jug to do anything else. It worked well this way, based on fermentation starting quickly, even in a lager at 48°F.
Even if I had a choice, I'd probably do it this way again. It avoids stressing the yeast by keeping them in contact with all the alcohol from the spent starter, and also keeps your starter wort gravity closer to the wort you made up. I'm not sure what effect, if any, dilution would have on the reproduction.
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