Yes genetics CAN degrade over time but nothing sais it will at a particular time. Its all in probability.
I have a genetic chart for every clone and plant that make it possible to follow it back to its original seed and I will never take clones to use for production that is more than 2 generations away from the original seed.

As it is now I took clones from all my seed bred plants. I put them in 12/12. 5th week of bloom I selected which one had the best traits and threw out the non corresponding clones and made mothers of the clones from that plant.
I have to be VERY unlucky to have a genetic degrade in fewer than 4-10 generations from seed purelly mathematically so if I stay at first to 2nd generation I will by all probability be in the safe from that problem. And, since a good kept mother can be kept for 5-10 years I'd say its unlikelly I will have to worry about my WW genetics for quite some time if I don't loose all my plants at the same time. Worst case I have to go to third generation cloning for some years before I do a new search for a superfemale from a seed grow.
Next step for me atm is to do a sative seed grow during the winter at some point and from there try to find a good mother as well so I have White Widow, Hindu Kush (already making a mother of that) and then a 3rd strain from a sativa I have not decided on yet. Strawberry Cough or Arjans Super Silver Haze #3 (very nice smoke and the lowest sativa in the world) as I think now. Time will tell.

Puffzter