So does that mean I have to disable Teatime or uninstall S&D and reinstall it without TeaTimer somehow?
No, I'm not making any recommendation, just an observation. It is just saying that contrary to what YoKenny said Teatimer isn't redundant just because you have SAS, because the free version of SAS doesn't have any resident function, so teatimer could provide limited resident functionality.
There is however IMHO such a thing ad you can get too much of a good thing and that includes security software. Given that you have avast which does have anti-spyware built in and two on-demand anti-spyware scanners (SAS and MBAM), perhaps that is enough (perhaps S&D is redundant), see my signature.
For immunization as Tech mentions you could use SpywareBlaster which has an immunization only function the program doesn't run in the background consuming resources.