Sorry if I came off flippant, I didn't mean to. I just know multiple people (both the two professionals with tiling companies older then me and casual do-it-yourself tilers) have seen my basement and all of them have said the exact same thing. So I have to trust what everyone who has seen my situation says.
With that said a little background. The house was built in 1999, walls are ICF (concrete filled). Floor is smooth trowled with stress cuts as mentioned (that end a few inches from the walls). The one side had some water coming in but it was due to the previous owner building a stone patio the year before I bought the house that was too tall and was pooling water to the point of going "over" the poured foundation (up under the siding and between the concrete and rim joist). I fixed that issue and it's been pretty dry until early last month. The area had a weird couple days where the ground was fully saturated, there was snow on the ground, and a huge thunderstorm came through. Both my utility and toilet drain (no toilet yet) in the basement started back feeding storm water (thankfully it was 99% clear water with some silt...smelled like decaying leaves) and we ended up with about 6 inches in the basement.
I talked to the sewer department who came out that morning and pretty much said they have never seen this much water in the system ever in there time working for the village and houses all over the area are flooding. I talked to the previous owner and asked about flooding and they said it never had happened before. I then checked with neighbors and it was spotty...one year one house did it and the others were fine, another year a different house did it and the others were fine (were in a small 11 lot "development"). Looks like it was just my houses turn. I have been working on finishing the basement for over a year now (Re: http://www.diychatroom.com/f18/finishing-basement-need-review-plans-59302/
) and thankfully nothing was ruined. I got the water out (thank you walkout basement with big sliding door) and the drains stopped back feeding about three hours after they started. A couple shop vacs, couple dehumidifiers, and a very long 14 hour day and the basement was fine with no real damage other then some mudded joints near the floor that started to suck in which will be covered with base molding.
So now I want to do tile because I don't want to have to go through ripping out carpet in the very slim chance it happens again. I had just finished tiling and sealing my 50 sq/ft bathroom down there and it was a breeze to clean after the flood...shop vac, quick mop, and done ten minutes later. All the water just beaded up on the surface and none of the black silt got into anything because of the sealing. The bare concrete however took all day with shop vacuuming, scrubbing, rinsing off, sucking it back up, then finally running a carpet cleaner over it to get whatever was left (which it turned out was a lot).
With that said I will put tile down either myself or hire someone to do the actual tiling portion and I'll do all the prep. so anything anyone can suggest to "minimize" problems would be great. I plan on buying a extra 50 sq/ft of tile for backup if the floor does move and in case something breaks. The tiles I'm going with will be 18" x 18" and installed in a diamond formation. I've been doing more reading and I'm thinking of sealing the stress cuts the same way I thought about (backer rod and flexible caulk) then I'm going to fill in the one low spot (the 1/16" one) with a self leveling thinset material so I don't have to purposly add extra thin set during install. Lastly I'm wondering if it would be worth coating the entire floor with something like RedGard and using it as a crack prevention membrane. The cost would be around $250 for the entire basement, half that to do all the stress cuts and the recommended distance on each side of them (which is the diagonal length of the tile so 25.5" on each side). Anything else I can do?