yes he can stormnut, though that has nothing to do with what kk is saying. I don't know what part of that link you posted makes you think otherwise.
By 1967, however, the Court would note that "the major premise of Adler has been rejected." In its place was a new premise: that the government ought not to be able to do indirectly what it cannot do directly. The Court took the position that public employment cannot be conditioned on a surrender of constitutional rights. The problem for the Court then became how to balance the government's interest in maintaining an efficient public workplace against the individual employee's interest in free expression.
Pickering v Board of Education considered the case of a public school teacher fired for writing a letter to a newspaper critical of the local school board. In ordering the teacher reinstated, the Court found that a public employee's statements on a matter of public concern could not be the basis for discharge unless the statement contained knowing or reckless falsehoods, or the statements were of the sort to cause a substantial interference with the ability of the employee to continue to do his job.
Mt. Healthy v Doyle also involved a fired school teacher. Doyle lost his job after calling a radio station disc jockey to complain about a memo sent to school teachers concerning a new teacher dress code. Because Doyle had given the district other reasons for terminating him (such as giving "the finger" to two students), the Court remanded the case for a determination as to whether Doyle would have been fired even if he hadn't engaged in the protected expressive activity of calling the radio station. If he would have been fired anyway, the termination could stand, the Court said.