A new update to FamilySearch.org's Family Tree allows you to search for and then add sources directly to an individual from the Historical Record Collections. When you sign in to Family Tree and click on an individual to see their Details Page, you will see a new link under the heading for Research Help with a link to Search Records. Here is a screenshot showing the link:
Clicking on the link takes you directly to a Record Search with the information from the Details Page already filled into the search parameters. Here is an example:
As an example, I could now choose to click on the entry for Sophia Overson in the 1880 U.S. Census. This shows the following record:
The arrow shows where you can click further to Attach to Family Tree. Clicking on this button brings up a question asking whether any of the suggested people match your person?
One more level of checking to make sure the Record will be attached to the right person shows if you indicate that you have the right person:
If you have been opening multiple tabs, like I do, you will have to refresh or reload your Details Page to see the attached source. Once you have attached the source, it shows in the Sources section of your ancestor's Details Page.
A copy of the link to the source also shows up in your Source Box. This procedure eliminates a couple of steps in the process of attaching files, but it also allows the source to be attached to others listed on the same source. It seems to me that FamilySearch is contemplating adding a specifically identified source to each person in the Family Tree. So you would search for a record individually named for each individual. However, this is a significant waste of time since you have already searched for and recorded a source one of the family members. I see no reason not to use the same record over and over for different members of the family that show up on the source record.