  The mechanism of the roughening induced partial depinning of gliding
dislocations from Helium-3 impurities is proposed as an alternative to the
standard "boiling off". We give a strong argument that Helium-3 remains bound
to dislocations even at large temperatures due to very long equilibration
times. A scenario leading to the similarity between elastic and superfluid
responses of solid Helium-4 is also discussed. Its main ingredient is a strong
suppression of the superfluidity along dislocation cores by dislocation kinks
(D. Aleinikava, et. al., arXiv:0812.0983). These kinks, on one hand, determine
the temperature and Helium-3 dependencies of the generalized shear modulus and,
on the other hand, control the superfluid response. Several proposals for
theoretical and experimental studies of solid Helium-4 are suggested.
