I am not saying that penny packets of B-29s to Europe was a good idea, it would not have been. I am saying Groves' expertise was in engineering and construction management - very talented but not an expert in "everything". BTW at one point in my life I was trained in targeting, and using nukes.
The point of using nukes was not to be better at the destruction of German economic targets, it was to city bust and shock the enemy in to submission - exactly the effect in Japan. The UK and the USA were certainly not averse to doing this, even if the idea was to destroy the city to destroy the industry/target because precision bombing wasn't doing this - think Dresden. If you are talking about an AANW Germany, or one where the eastern front is relatively quiet due to some sort of peace/armistice, or one where 2nd generation jets work without needing a new engine all the time and Wasserfall missiles work and are available in large numbers, then sure B-29s over Germany in 1945/46 are not going to work.
There are ways to mask the nuke carrying bomber, like a single plane at night or breaking off from a larger raid at a relatively close by city/target. These will work a couple of times before the Germans wise up. In any case if the war is going on in 1946 with a Germany not already in bad shape from conventional bombing and not drained and dealing with Russians advancing from the east and no western powers closer than Rome the strategic calculus is different.
The point of using nukes was not to be better at the destruction of German economic targets, it was to city bust and shock the enemy in to submission - exactly the effect in Japan. The UK and the USA were certainly not averse to doing this, even if the idea was to destroy the city to destroy the industry/target because precision bombing wasn't doing this - think Dresden. If you are talking about an AANW Germany, or one where the eastern front is relatively quiet due to some sort of peace/armistice, or one where 2nd generation jets work without needing a new engine all the time and Wasserfall missiles work and are available in large numbers, then sure B-29s over Germany in 1945/46 are not going to work.
There are ways to mask the nuke carrying bomber, like a single plane at night or breaking off from a larger raid at a relatively close by city/target. These will work a couple of times before the Germans wise up. In any case if the war is going on in 1946 with a Germany not already in bad shape from conventional bombing and not drained and dealing with Russians advancing from the east and no western powers closer than Rome the strategic calculus is different.