But in 2016 riding all the Tour was a good preparation because they had an extra week and also fly to Brasil with a positive time difference is a lot different compared to fly to Japan with a negative time difference, if you take a flight on Monday morning you'll be in Tokyo when it's already the following morning there (and should be a direct flight otherwise could be even 15/18 hours of travel only) and that shorten also the recovery time, in addition to the jet lag and the weather, so I don't think the fact that Valverde is one of the few that is always good in San Sebastián after the Tour can be used as reference. Maybe he won't be a dead man walking like the ones that in normal years aren't even able to perform in San Sebastián coming out of the Tour but he'll be hampered compared to the ones that will leave the Tour early or will come from a different approach that enable them to fly to Japan earlier.
I'm not entirely sure it's the smartest of ideas, however, if he's the one that wants to do it, they aren't going to say no to him. In 2016 he also raced San Sebastian before going to the Olympics. If I'm reading correctly what is being said, is that he wants hard racing right before the Olympics which if he doesn't race the Tour he's not getting or doesn't think he's getting. IMO, racing 2 weeks to maybe into the 3rd week of the Tour is likely the best prep for the Olympics. However, I'm not sure you're going to find many who would be allowed to do that.