Most modern weapon designs are actually fission-fusion-fission designs with most of the energy actually coming from the final fission step - the latter being driven by neutrons from the fusion step. Things get even more complicated with the fact that primaries are fusion boosted fission and the fusion step contains a fission "sparkplug".
Sure, but the fusion step is still important and somewhat poorly understood, so ICF experiments which mirror the conditions inside the fission-fusion step could be valuable for increasing yields.
Interestingly, a lot of recent developments in warhead design (e.g. the non-spherical primaries of the W-88) are actually about primary design - so I guess its possible this kind of research also feeds into the fusion boosting component of primaries.
