what processes could be done (applied) with Point lasso tool?
I recently used other photogrammetry software, and there was able to clean the dense cloud with lasso tool.
I often use it to select cameras to check which ones are not aligned in the component.
Also, you can display the points relating to one or several cameras by pressing X.
The other way round works too - select some points and press S and VOILA: all associated cameras are selected!
I use it to figure out which cameras have alignment problems for example.
Hope that helps.