This series is an example of that but still shocked and surprising to see England end in a whitewash.
LOL.... Bangladesh is anything but consistent. They perform pathetically whenever they play in SNEA conditions. And apart from Shakib al Hasan, they don't have someone who performs consistently (although Litton Kumer Das is showing a lot of promise lately). England was whitewashed because of their own weaknesses. First of all, they didn't made the proper preparations once they landed in Bangladesh. And secondly, their spinners couldn't make use of the helpful pitch conditions and trouble the Bangladeshi batsmen. And finally, the England batsmen were clueless against the Bangladeshi spinners.
Stats of Bangladesh on there home ground are always better then how they perform elsewhere. They even have whitewashed Pakistan in ODI series played in Bangladesh few years back.
PCB must learn something from this, even Bangladesh prepare home pitches that suit them. We have seen pitches in Pakistan that resulted in the loss of 3 consecutive home test series.