Yes, there are several strategies that can be used to reduce the undesired insertion of multiple primer fragments in plasmids generated by inverse PCR. 1. Use a different set of primers with lower annealing temperature. 2. Increase the stringency of the PCR reaction by increasing the denaturation temperature and/or reducing the extension time. 3. Increase the number of PCR cycles or use a longer PCR product as template. 4. Ensure that the PCR reaction is not contaminated with residual primers or other contaminants that might interfere with the reaction. 5. Use a different enzyme with more stringent proofreading properties. 6. Use a higher concentration of template DNA. 7. Use a proofreading polymerase and a hot start PCR. 8. Use a higher annealing temperature and a lower extension temperature. 9. Perform the PCR reaction in a thermocycler with touch-down cycling. 10. Use a PCR product that is shorter than the primers used.

Yes, it is possible to reduce the likelihood of undesired primer fragments being inserted into plasmids generated by inverse PCR. One way to do this is by ensuring that the primers used have a low degree of homology with the primers used in the initial PCR. Additionally, the primers should also have a low degree of homology with the plasmid vector itself. It is also important to use a high-quality enzyme, such as Phusion, to ensure that the primers are correctly annealed and that the DNA strands are correctly ligated. Finally, it is important to use a high-quality PCR buffer to minimize the likelihood of nonspecific binding.