>>>the ONT-PHX-ABQ run, they load up 35,000 or so pound of fuel to run both legs.
Pull this on a 737, and you're going to be arriving in ABQ with about 25,000 fuel aboard, which (depending upon what model of 737 and the ABQ temperature is) will very likely leave you overweight for either performance-limited landing weights, or maximum quick-turn landing weights.
Bottom-line: Thou must watch thy tankering fuel into "hot-and-high" airports, lest thou sitteth eons awaiting to defuel...
Otherwise, Rick said it all... FYI, "fuelstops" are really another thing, defined as planning to go ABC-XYZ on a scheduled flight and it can't make it non-stop for some reason (high payloads, etc.), and you have to "fuelstop" someplace in between.
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