shawndo wrote:I believe the time it takes for both are around the same.
For a full-bodied, balanced ristretto, I must allow more pour time than a double (e.g., 25 seconds vs. 35 seconds).
Al's Rule elaborates on this guideline.
The Wikipedia article you cite proposes two ways of pulling ristrettos other than simply grinding finer and extending extraction time: Cutting the shot early and tamping harder (?!). The first alternative suggestion is obviously a shortcut that compromises the ristretto's taste balance by making it front-loaded; the second alternative suggestion, in my experience, is fiction.
Wikipedia wrote:One modern method of "pulling" a ristretto shot is to grind the coffee finer than that used for normal espresso, and pull the shot for the same amount of time as a normal shot. <snip> ...Another modern method for pulling a ristretto is to simply stop the extraction early, so less water has time to pass through the ground coffee. <snip> ...A third modern method, that serves as a compromise between the previous two, is to prepare the shot without adjusting the grind but to use the tamp more firmly.