Well, as we know, oil needs to be at least warm if not hot when extracting it from engine so it will become thinner and enable us extract almost all dirt with it. Of course, this means that we are going to run the engine prior to oil change. Then again, when you need to measure the oil level, you measure it in the morning after the engine is not being run for at least over night so that all oil is being returned to the sump and the bigger the engine the longer will it take. So, therefore is the difference I presume. So, it makes sense that it will be a bit harder start on engine if you take it all out, but for oil it will be better to be clean, so it is compromise and do what you prefer. My procedure after oil change to prevent harsh start on engine is to disable positive wire from fuel shut off valve and crank the engine until the oil pressure does not show up, then I reconnect the wire and fire up the engine. Then again, this procedure is hard on starter and battery so you should not crank the engine for longer than 15-30 seconds without at least 1-2 minutes pause between cranking if so needed. There is always something and the list can go on indefinitely (i.e. now add oil filter to the procedure,...).
Anyway, you will most definitively better extract oil by taking it from the bottom of sump.
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