I think Channel 2 is being hypothetical and positing ops in uncontested airspace where F-35 can load up the external pylons. It's a slightly fictional scenario whereby we use F-35 for one day to destroy completely the air-to-air and surface-to-air threats, put them all away until the next war and get out the 105s.
If the only metrics are farther, faster, heavier, then the question is already answered. If the question takes the whole issue in the round, then you're unlikely to get to day 2 in time for farther, faster, heavier to be any kind of advantage.
But like I said, it's a hypothetical "what if".