Five penalty runs

Sri Lanka were docked five penalty runs in the third session of the second day
at Pallekele, following a strange interpretation of the law
governing deliberate short runs by the umpires.

Law 18.5.1 states that:

"If either umpire considers that one or both batsmen deliberately ran short at that umpire's end
the umpire concerned shall, when the ball is dead, call and signal Short run and inform the other umpire
of what has occurred and apply [five penalty runs]."

Here's what happened :

www.espncricinfo.com/story/_/id/25282594...s-one-short-incident

Roshen Silva was batting alongside Akila Dananjaya
when Roshen cut Jack Leach fine of Moeen Ali at short third man.

That was unfair ?