During the last three days of strikes there were about five return flights cancelled so in terms of cancellations it's having next to no impact.
Whilst I support better T&Cs for MF, it's notable that some of the loudest voices elsewhere egging on crew to strike are from those who went on strike in 2010 and have been against MF from the start. There is definitely a sense of some seeing this as unfinished business and actively wanting to see MF destabilised.