Pat writes:

How would a recumbent handle the Tour?

You mean, if the UCI rules permitted the use of recumbents?

They'd like have some advantage on flat breakaways and time trials,
but the disadvantages in sprinting and climbing would scupper them
compared to regular bikes.

Another factor is that recumbents are heavier than regular bikes,
although there are now some 20-22 lb recumbents (e.gg., Bacchetta)
that can be bought by Joe Everedge. That would go a long way towards
improving climbing. My friend Don's titanium Bacchetta seems to work
pretty good on climbs.