Hi Korzy,
As you probably know already, RoT= Rule of Two and requires 1 tactic for away and 1 tactic for home; RoO = Rule of One and requires that individual player's mentality differ only by 1 at a time - By that I mean if GK's mentality is set to 3, DC's meantality shld be 4, FB 5, DM 6, Winger 7, AM 8, Striker 9.
So combining the two theories, I have two tactics each utilising the RoO mentality rule.
The mentality numbers above is actually my away tactic (or the attacking-away tactic as discussed by wwfan before), this works wonders for me when I am always favourites to win comfortbally away (when I am liverpool/milan). Depending on the prematch odds and how offensive the opponent formation is, I might adjust the mentalities down pre-game, i.e. go 1 notch down for each individual mentality when pre-match odds say I am the slight underdog: so it becomes GK 2, DC 3, FB 4 and so on.
My home tactic has my GK on 10, DC 11, FB 12, DM 13, Winger 14, AM 15, striker 16. This has almost always worked. Sometimes if I am underdog at home and the opposition gives me an offensive formation, I adjust all mentality by 1 notch - thus going more defensive.
So...going more defensive for me involves mainly clicking 1 notch down (2/3 notches down can work sometimes too)for each player -takes about 3 secs to tweak those. I do it during the match when the opposition goes more offensive. I also adjust forward runs so that FBs and DMs are on rarely. I never adjust passing/tempo/width unless opponent goes 4-2-4.
I always have a deep d-line no matter what (doesn't work in current 08 engine
coz of closing down bug).
If you start with my mentalities and then realise that in the 1st 10-15 mins or so you lose a lot of possession and the opposition gets a lot of chances, it is best if you adjust your mentalities quickly. Normally I just do 1 notch down and it works. Sometimes it involves clicking conter attack on to counter offensive 4-2-3-1, 4-3-3 or offensive 4-4-2. How to tweak and when to tweak is 1/2 trial and error and 1/2 experience +luck

So even though the above sets work the best for me, you may find that for your team u need some adjustments (e.g. lower mentality if you have a weaker team).
Hope these help.