Even in my small area of astrobiology, the design of a single mission to find habitable planets orbiting other stars requires substantial input from the studies of astrophysics, space communications, space flight technology, optics, materials science, the interplanetary space environment, Earth's atmospheric system, microbiology, geology, computing, remote sensing, and signal processing. Within each of those areas, input from many sub-disciplines is required. For example, in the "astrophysics" portion of my work I communicate from astronomers from all across the field. Some of them know all about the variability of stars, some of them know about the multiplicity of stars and giant planetary companions. Some of them are experts in the details of previous observing campaigns that have collected the data that I now need. And this process of information gathering goes on and on. In science, we need people who can go deep, and people who can go broad. My colleagues and I can literally create new knowledge and capability simply by networking and pooling our talents. I am the kind of person whose purpose in the community is to build bridges between areas of knowledge and begin unfolding the bigger picture.
The appropriateness of cross-disciplinary sharing depends entirely on the situation to which your knowledge is being applied. The Fire Department does not need my knowledge of astronomy in order to douse a chimney fire, but they might like to know and prepare in advance if an asteroid is about to impact our town!
Cross discipline sharing, is often a very positive and necessary thing to get experiment done. But cross discipline peer review of theory seems (to this outsider) often a very threatening thing and off-limits. Astronomers, elementary particle physicists, general relativists, solid state physicists, etc. ignore inconvenient criticism even from world class physicists in other subspecialties and politely abstain from criticizing other subspecialties.
Silence seems to be the correct response to rare criticisms such as Roger Penrose's "What reason is there to believe that an inflationary picture of the universe is likely to be close to the truth? Despite its evident popularity, I wish to give my reasons for casting considerable doubt on the entire idea."
Most physicists and astronomers know that very little is to be gained (from a career point of view) by expressing criticism outside of one's own discipline. This could be called the "Physics censorship hypothesis."