Como bloquear chamadas IO no Mono

Eu tenho métodos utilitários parecidos com este.

    public static WebClient.ResponseSpec retrieve(final String baseUrl, final Duration responseTimeout) {
        // ...
    }

    public static <T> Flux<T> retrieveBodyToFlux(final String baseUrl, final Duration responseTimeout,
                                                 final Class<T> elementClass) {
        return retrieve(baseUrl, responseTimeout)
                .bodyToFlux(elementClass);
    }

    public static Mono<Void> download(final String baseUrl, final Duration responseTimeout,
                                      final Path destination, final OpenOption... openOptions) {
        return DataBufferUtils.write(
                retrieveBodyToFlux(baseUrl, responseTimeout, DataBuffer.class),
                destination,
                openOptions
        );
    }

Agora quero adicionar outro método para o cliente consumir um arquivo temporário.

    // Let me download the file, and you can just cononsume the file!
    public static Mono<Void> download(final String baseUrl, final Duration responseTimeout,
                                      final Consumer<? super Path> consumer) {

        // Create a temp file
        // download the URL to the file
        // accept the file to the consumer; possibly blocking IO operations
        // don't forget to delete the file!
    }

Como posso fazer o trabalho sem nenhum aviso de bloqueio de chamada?

Eu tentei (e parece funcionar), mas estou me perguntando o que estou fazendo. É ideal? Eu tenho outras maneiras?

        return Mono.usingWhen(
                        Mono.fromCallable(() -> Files.createTempFile(null, null)).subscribeOn(Schedulers.boundedElastic()),
                        p -> download(baseUrl, responseTimeout, p, StandardOpenOption.WRITE)
                                .then(Mono.just(p))
                                .doOnNext(consumer).subscribeOn(Schedulers.boundedElastic()),
                        p -> Mono.fromCallable(() -> {
                            Files.delete(p);
                            return null;
                        }).publishOn(Schedulers.boundedElastic()).then()
                )
                .then();