In embodiments, improved capabilities are described for dimming performance of lighting methods and systems, such as the improvement of dimming LED lamps that are dimmed from standard external dimming devices. Methods and systems for improving dimming performance include a fast startup override facility for overriding a default dimming function of the lamp's electronics through forcing the lamp electronics to operate with a higher than normal duty cycle to ensure the lamp electronics can deliver higher than normal power to an LED module during a dimming current level startup condition. Dimming facilities may also include a dynamic RC selection facility, an active N-level bleeder facility, a dimmer-type detection facility, an improved dimming linearity through symmetrical phase cutting facility, and a flicker reduction facility.