“It should be based on currently accepted principles of physics
and reasonable technology extrapolation
(no cold fusion, matter/anti-matter, P-11B, worm holes etc.)”

This really bothers me. It either shows a complete lack of understanding about these 4 concepts… or a deliberate attempt to divert attention away from pB11 as a competitor.

Worm Holes don’t exist naturally close enough to Earth to use them. And the very scientists who hypothesize creating artificial wormholes know that it would take more energy than our whole sun contains to produce.
Matter/antimatter is not viable because it requires more energy to create than it would release. We cannot simply convert matter into antimatter.

Cold Fusion does not even have a credible hypothesis. But was discredited.

pB11 may not be a reality yet, but there is no physical law saying it can’t be done. If deuterium fuse, so can pB11. It just takes more energy.
We already know that Boron-11 fuses…. we have done it in particle colliders. So this concept is no where near the 3 others.

It truly seems like a deliberate attempt to divert attention away from pB11 as a competitor. They might be worried that aneutronic fusion may get the spotlight soon. And if LPP or others succeed, the funding for their project might dry up considering DPF does have space propulsion potential.