Perhaps it did when it was first published but that joke isn’t funny anymore.
I’ve seen it criticised for being racist or colonialist but I don’t think it is. It’s just not as amusing as it pretends to be.
I usually love Waugh’s novels: Brideshead Revisited is sublime. Yet, for me, this one misses the mark.
It hinges on mistaken identity and further misunderstanding. There is more wool pulled over more people’s eyes here than in a changing room in a knitwear shop.