Why bother to agree on dispute settlement?

Should the parties to an international contract try to specify, in the contract, a method for the settlement of disputes that arise from the contract?   

The simple answer is: yes, to save time and money.  If the contract does not specify how to handle disputes, one party will probably commence litigation in its local courts.  We might think that party has an advantage, but in fact courts do not automatically accept cases involving defendants from other jurisdictions.  Instead, they will often examine the matter involved (in this case the contract and its performance) to see which country has more, and stronger, connections with the case.  For example, they will ask where the contract was negotiated, where it was signed, and where performance by each party occurred. Regarding the signing of the agreement, they will usually ask where the second of the two parties signed it, because in most cases it is not a contract until the second party signs.  It is possible that the first court approached by the plaintiff will say that foreign law applies or will even say that the appropriate court for hearing the case is a foreign court, where the defendant is located.  The analysis involved is called a "conflicts of law"  analysis, and the defendant will typically argue this matter strongly, with the result that the first $50,000 to $100,000, or even more, of each party's legal costs will be spent on these preliminary questions of law and location.