What is the impact of a contract that is varied at will?

See also comments of Anderson J. in Dal Santo v. Dal Santo (1975), 21 R.F.L. 117 (B.C.S.C), at p. 120: It is of great importance not only to the parties but to the community as a whole that contracts of this kind should not be lightly disturbed. Lawyers must be able to advise their clients in respect of their future rights and obligations with some degree of certainty. Clients must be able to rely on these agreements and know with some degree of assurance that once a separation agreement is executed their affairs have been settled on a permanent basis. The courts must encourage parties to settle their differences without recourse to litigation. The modern approach in family law is to mediate and conciliate so as to enable the parties to make a fresh start in life on a secure basis. If separation agreements can be varied at will, it will become much more difficult to persuade parties to enter into such agreements.