This strike will affect us; not just my Saturday football, which is neither here nor there really, but also Mrs O will have to cancel a potential trip to London to see G/S's first meeting with Father Christmas.
They will run some sort of service on the strike days, using non-union staff, but it will be in the 50-75% region.
I do feel sorry for commuters (like Meriad, I believe) but hopefully they will get some sort of reasonable service - SWR will concentrate on running commuter routes. Our Exeter - Waterloo route will go from hourly to 2-hourly and will be totally, totally rammed, hence I've really had to advise Mrs O not to risk it - she couldn't physically fight her way onboard / stand for a long period of the journey (I have had to do this the last time I travelled during a period of major disruption).
All that said - personally, I do think the RMT have a point with their argument over who opens/closes the doors. It's primarily a safety issue, but also there is the long term aim by the company of getting rid of guards and moving to fewer and lower-grade "Customer Service Operatives".
I also would not trust South Western Railway as a company one inch - they have refused to honour pledges made to the union and have prevaricated with negotiations (now nearly 2 years) throughout. Overall, I'm afraid, I support the strike.