Costs are going to get competitive over time

sure they are. in the 25th century, or by the 29th century for sure, if not by
the year 4,000.

Even when you include a
small genset for the "diesel-electric" approach there's a big win in the long
term "total cost of investment."

*if* total cost of investment means total cost of investment the breakeven
point may never be reached.

but keep hoping and praying.