example in flashvars

fexp: "913555,904461,916611,922401,920704,912806,927201,922403,925003,913546,916805,920201,901451", //Experiment IDs

this is a nice feature to roll new features only on specific videos, they implement this in the player then in production for specific videos
they try gradually new features and if something doesn't work they can just stop remotly

for explanation see: com/google/youtube/model/YoutubeEnviroment.as (line 738)

908476 = adaptiveExperiment (Adaptive streaming)
908477 = adaptiveExperiment, useDualSplicers
913529 = adaptiveExperiment (Adaptive streaming)
908456 = adaptiveExperiment, fastSpliceExperiment
918011 = adaptiveExperiment, fastSpliceExperiment, tagQueueReadaheadExperiment
908457 = adaptiveExperiment, consider720LowDef (haha: my eyes creep out at 480p everything below is low-def :smile: ) 
908488 = openChunksEarly
908491 = openChunksEarly, adaptiveExperiment
904429 = stageVideoForbidden
909709 = plusOneInlineAnnotationExperiment
904448 = tagStreamingForbiddenExperiment
913553 = tagStreamingForbiddenExperiment
913408 = gradientEndScreenExperiment
913416 = darkGradientEndScreenExperiment
913411 = moreAudioNormalizationExperiment
913413 = widescreenEndScreenExperiment
913414 = mqThumbnailHoldback
904827 = videoStatsVersion2Experiment
908467 = useRaceConditionWorkaround
913559 = vssResumeableExperiment
925108 = halfSpeedPlaybackExperiment

904701, 904706 = defaultBufferLengthValue = 0.5
904702 = defaultBufferLengthValue = 1
904703 = defaultBufferLengthValue = 1.5
904704 = defaultBufferLengthValue = 2.5