The summary table is correct. The text under Remarks is vague and misleading...hard to say whether it's "right" or "wrong."
Here is how I'd phrase it:
/all = Normally TFS checks whether your local version (i.e. the version you received last time you ran Get or Unshelve) is different from the version requested by the /version parameter, in order to avoid unnecessary downloads. Passing /all bypasses this check. This might be necessary, for instance, if you manually deleted the file from disk instead of via TF Delete.
/overwrite = Normally TFS will file a conflict when it encounters a file that (a) needs to be redownloaded due to mismatched versions or the /all parameter (b) does not have the +R filesystem attribute (c) does not have a pending change. Passing /overwrite bypasses check (b). This might be necessary, for instance, if you modified the file in an editor that doesn't have TFS integration.
/force = Combines /all and /overwrite.
In practice these switches are dangerous and inefficient. You will save yourself a lot of headache and bandwidth by the Power Tools (tfpt online / treeclean / scorch) instead.