This
blog post from Eero Tuovinen gives another take on the approach to consequences and pacing/drama management that "fail forward" is generally associated with as a technique:
The actual procedure of play is very simple: once the players have established concrete characters, situations and backstory in whatever manner a given game ascribes, the GM starts framing scenes for the player characters. Each scene is an interesting situation in relation to the premise of the setting or the character (or wherever the premise comes from, depends on the game). The GM describes a situation that provokes choices on the part of the character. The player is ready for this, as he knows his character and the character’s needs, so he makes choices on the part of the character. This in turn leads to consequences as determined by the game’s rules. Story is an outcome of the process as choices lead to consequences which lead to further choices, until all outstanding issues have been resolved and the story naturally reaches an end. . . .
The GM . . . needs to be able to reference the backstory, determine complications to introduce into the game, and figure out consequences. Much of the rules systems in these games address these challenges, and in addition the GM might have methodical tools outside the rules, such as pre-prepared relationship maps (helps with backstory), bangs (helps with provoking thematic choice) and pure experience (helps with determining consequences).
To given an example of a rules system that is intended to help with figuring out consdequences, Burning Wheel requires action declarations to be expressed in terms of
intent and
task. If the check succeeds, the task succeeds and the intent is realised. (This is important: there are no successful rolls that nevertheless fail to realise intent because the GM calls for a further check, or introduces additional secret backstory into the mix.)
If the check fails, the GM gets to narrate what happens. Failure can be a failure of task, or a failure of intent - in the latter case, the GM is
expected to introduce additional hitherto-secret backstory into the mix. The GM advice encourages the GM to focus on intent rather than task in narrating failure, because of the way this will tend to support narrative dynanism (what Tuovinen calls "choices lead to consequences which lead to further choices"). The GM is expected to draw and develop the hitherto-secret backstory out of the already-established context of play and backstory (which the players will have had an important role in establishing) - not to just make stuff up arbitrarily out of whole cloth. Other parts of the rules systems come into play here - eg the rules whereby player establish Beliefs and Instincts for their PCs, the rules whereby the table as a whole votes on traits for characters, the relationship rules, etc. These all contribute context and content for determining new backstory that fits in terms of both theme and content.
Another important rule in BW action resolution is "Let it Ride" ie once a check has been made and a consequence determined, it stands. For successes, this is a limit on GM power. For failures, it does two things: (i) it prevents players engaging in retries, and forces them to rethink their approach to the situation; (ii) it creates a further incentive for the GM to narrate failures in such a way as to open up opportunities for new approaches to be deployed.
There are versions of D&D which, in my view, lend themselves more towards a similar sort of approach than others. Original Oriental Adventures, for instance, has fairly elaborate relationship rules, plus a thematically rich backstory to which many PCs (eg shukenja, monks, kensai, samurai) will be connected. The hit point rules for combat create a sort-of "Let it Ride" in that domain; although the actual rule book has only limited advice on how non-combat proficiencies are meant to work, the BW approaches of intent-and-task and let-it-ride could probably be applied.
4e also has a thematically rich backstory to which many races and classes are connected, which helps with the backstory stuff. Skill challenges provide a framework within which intent-and-task can be readily applied. Stephen Radney-MacFarland had a Save My Game column for 4e advocating let-it-ride as an appropriate approach to the game.
To give a contrasting version of D&D: Moldvay Basic, at least as set out in the rulebook, doesn't lend itself especially well to this sort of approach. There is little or no emphasis on PC backstory, which means that the material for narrating consequences other than as spun out of whole cloth is not there. There is no general action resolution system to which intent-and-task can be applied. And rather than let-it-ride, the issue of retries and pacing is meant to be managed through a system of GM timekeeping combined with wandering monster rolls. (Upthread, [MENTION=87792]Neonchameleon[/MENTION] pointed to the similar features of original D&D.)
Unlike OA or 4e, I don't think this is a game system in which "fail forward" can be straightforwardly applied.
I'll leave it for others with more experience to reflect on 3E and 5e in this context.