/title clear command doesn't work

the /title @p clear command is supposed to clear the screen from the titles, but it doesn't do it.

 the 2nd command block (the "/title @p clear" one) said that the command was executed successfully but nothing happened. 

steps to reproduce

1)  put the "/title @p title test" command in a command block

2) put the "/title @p clear" command in another 

3) execute the first and after the second