I wrote a Zymurgy article - last year? two years ago? - on express brewing or how to turn a beer around in 10 days or less.
The basics for most homebrewers come down to:
- Gravity - lower is better
- Fermentation control - lower is better
- Transfer - being johnny on the spot - most brewers are lazy
- Cold Crashing / Clarifiying - absolutely critical if you want to turn thigns around
- Yeast Choice - some yeasts just need more time
- Ingredient Choice - the odder you go, the more time you'll probably need
And yeah, Belgians typically take more time, but I can turn around a
Saison Ordinaire in about 10 days if I need to. Along with IPAs, milds, etc.