revise docs

Author: ywelsch

docs/reference/modules/transport.asciidoc

@@ -86,24 +86,22 @@ example above:
 * `tcp.keep_alive`: Configures the `SO_KEEPALIVE` option for this socket
 * `tcp.keep_idle`: Configures the `TCP_KEEPIDLE` option for this socket, which
    determines the time in seconds that a connection must be idle before
-   starting to send TCP keepalive probes.
-   Only applicable on Linux and Mac, and requires JDK 11 or newer.
-   Defaults to 60 on applicable configurations, and -1 otherwise, which does
-   not set this option at the socket level, but uses the default system
-   configuration instead.
+   starting to send TCP keepalive probes. A value of `-1` means not to set
+   this option at the socket level but to use the system default instead.
+   Only applicable on Linux and Mac, and requires Java 11 or newer.
+   Defaults to 60 on applicable configurations, and -1 otherwise.
 * `tcp.keep_interval`: Configures the `TCP_KEEPINTVL` option for this socket,
    which determines the time in seconds between sending TCP keepalive probes.
-   Only applicable on Linux and Mac, and requires JDK 11 or newer.
-   Defaults to 10 on applicable configurations, and -1 otherwise, which does
-   not set this option at the socket level, but uses the default system
-   configuration instead.
+   A value of `-1` means not to set this option at the socket level but to
+   use the system default instead.
+   Only applicable on Linux and Mac, and requires Java 11 or newer.
+   Defaults to 10 on applicable configurations, and -1 otherwise.
 * `tcp.keep_count`: Configures the `TCP_KEEPCNT` option for this socket, which
    determines the number of unacknowledged TCP keepalive probes that may be
-   sent on a connection before it is dropped.
-   Only applicable on Linux and Mac, and requires JDK 11 or newer.
-   Defaults to 3 on applicable configurations, and -1 otherwise, which does
-   not set this option at the socket level, but uses the default system
-   configuration instead.
+   sent on a connection before it is dropped. A value of `-1` means not to set
+   this option at the socket level but to use the system default instead.
+   Only applicable on Linux and Mac, and requires Java 11 or newer.
+   Defaults to 3 on applicable configurations, and -1 otherwise.
 * `tcp.reuse_address`: Configures the `SO_REUSEADDR` option for this socket
 * `tcp.send_buffer_size`: Configures the send buffer size of the socket
 * `tcp.receive_buffer_size`: Configures the receive buffer size of the socket