There are many understanding and experience based on what the texts say, and Buddhagosa mentiones the mental body which is a form of nimita I believe (I am no expert of the Visudhimagga so someone please correct or confirm please)
if you look elsewhere the Buddha uses the phrase "touches with their body" sometimes this is something which can be touched sometimes not, but it is meaning direct experience. however some meditators experiance a body others do not, there is a wide range of experiance regarding the same thing.
He who knows only his own side of the case knows little of that. His reasons may be good, and no one may have been able to refute them.
But if he is equally unable to refute the reasons on the opposite side, if he does not so much as know what they are, he has no ground for preferring either opinion …
He must be able to hear them from persons who actually believe them … he must know them in their most plausible and persuasive form.