I have been enjoying DWAITAS a lot for the past few months, running weekly games. The only thing thathas bothered me, somewhat, is that it seems that my characters never ever fail their rolls. At first i thought there was some "accidental" miscalculation of rolls going on but after a few weeks keeping check on that I found there wasn't.
So as an experiment, I shifted the difficulties a level upwards, adding +3 to each difficulty level.
The results, I found, added a bit more of an edge to the game in that there were a /few/ more failures then before but not so many that it upset the balance of the game. Also, characters were using their Storypoints more which, in turn, made them attempt more actual story oriented rp to EARN more storypoints. It has, to us anyways, made the game a bit more exiting when the odd rolls are used (this is a story telling game after all, and rolls have their place but should never rule the game)
Interesting advice there! It may very with different playing styles possibly. Such as games that have lots of task resolutions in them or games where the GM wants a more pulpy melodramatic feel an encourages grandiose spending of story points for climactic moments.
Interesting idea. Does this account for the degrees of success inherent in the system? (ie, success by 0-3 is a "Yes, but....")
It seems to me that an average person would have some difficulty in this sort of situation (granted, the Doctor doesn't tend to recruit "average" companions in the first place) - An average person doing a Normal task in their 9-5 job would probably have a relevant attribute and skill each at 3, so they'd need to roll a 9 (pretty hard) to barely succeed, and a 13 (that's just not going to happen) to succeed without any actual complications.
Of course, part of that depends on what you define as Normal - "Average guy" doesn't have to jump over a 6 foot chasm to escape their Cyberman pursuers, most days, but the idea that someone who's fairly skilled at driving (Transport skill of 3) having to roll a 9 to succeed at driving in morning traffic seems a bit extreme (granted, a 6 or higher is pretty much assured to be non-fatal)
This upping of the difficulties is what my group does as well. It makes even more sense for us, since in our role-play at any given time there's always at least one alien companion on the TARDIS. Also, while we do use the Yes, No, Yes-But, and No-But, we reserve the Fantastic Yes-And for double sixes and the Disastrous No-And for double ones, to make those extremes more significant when they happen.
Rather than changing the difficulty values, why not just change your evaluation of a situation? Maybe something you've been calling Normal should really have been Tricky all along, and so forth.
Also remember that difficulty levels assume an average person (attribute 3) with a competent or professional level of skill (skill 2–3) will succeed at a Normal task a little over half the time. If your group's characters are more or less capable than this the difficulty names aren't accurate.
Also consider making more use of the rules for taking more and less time. The GM has to set the base time; maybe you're letting the characters do things in too short a time.