From Wikipedia-
Robertson screwdrivers are easy to use one-handed, because the tapered socket tends to retain the screw, even if it is shaken.
[31] They also allow for the use of angled screw drivers and trim head screws. The socket-headed Robertson screws are self-centering, reduce cam out, stop a power tool when set, and can be removed if painted over or old and rusty.
[31] In industry, they speed up production and reduce product damage.
[31]
Their use is very common in Jayco and StarCraft trailer for the reasons cited above.
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