быть порукой — перевод на английский

All he wanted in the goodness of his heart was to write a book you could take into the toilet and defecate to whilst reading, but so honest did he make it, so honest was it, in its nakedly honest depiction of, for example, the time that Comedy Dave put a pound coin in the pub urinal, so honest was it that it literally forced the buttocks of the reader together, preventing them from carrying out the one purpose he had in mind for this book.