As a Gouken player, I rely pretty heavily of mix-ups and resets. In theory, a change in pace is pretty unexpected, so if you catch them mid air after something you would usually let land (knocking them out of the air etc) and then follow it up, they would be unprepared. 
 
In practice, though, (or even against my fucking flat-mates >_<) it never seems to. Either they just hold back, or hit reversal; granted I'll mix up the high and low attacksand throw out a grab sometimes, but if your opponent just mashes SRK regardless of whats happening (maybe thats a little harsh, I'm assuming sometimes I have mash too) then it seems a little pointless. 
 
Blocking after resetting seems the safest option, but its dull; rather than following up with something lethal and fairly...well, cool... you're left crouching expecting an uppercut.
 
I think this sounds a bit like I'm bitching, I guess I am a little, but (to sum up) if I haven't done a reset the whole round, and then I pull one off only to get headbutted/srk'd its irritating.

Any advice homies (stick a Glasgow accent on that and you'll have me to a tee).
 
On a side note, any other Gouken players? I need a fresh perspective (moving character helped for a while, Ken has improved my zoning).
 
Cheers
 
Edit: I'm watching a live stream of Kay0ss V Illiterate, and the Sakura player has tried to reset a handful of times, without a single one actually landing.

Alot of people who reset (Abel, Sakura ect.) will dash or roll at the last second to switch which side they're attacking from. That can throw off people who are blocking as they're falling thinking "Oh, I gotta block from the right" and then you dash under them as they fall and then they're blocking on the wrong side and you'll be able to hit them with a combo. Sakura does this alot and it's pretty effective.

Think of resetting as a really quick knockdown, you still have to follow it up correctly with a guessing game of which way to block, etc just like scooper says. The reason why this is good however, is if they guess wrong you have just reset the combo scaling and are that much closer to stunning them. Of course its all mind games, just like on the wake up game, the simplest thing you can do is bait them into throwing an srk if you can read the desperation from them.

Resetting is all based on player to player. If you use them all the time of course people will become savvy to them, if you use them more sparingly and do different things out of them you will inevitably catch them by surprise. Resets are always a gamble and in a lot of situations aren't even necessary.

Sakura has some really awesome resets. I had a friend on my list who used a reset-heavy Sakura. It was hard to judge which way she was going with her attacks, and I'd start downback charging, and she would end up on the other side and score another free combo and completely discombobulate me. Hm. I totally wanna pick up Sakura now, haha.