Fix --min/max-sleep-interval wording

youtube_dl/YoutubeDL.py

@@ -249,11 +249,16 @@ class YoutubeDL(object):
     source_address:    (Experimental) Client-side IP address to bind to.
     call_home:         Boolean, true iff we are allowed to contact the
                        youtube-dl servers for debugging.
-    sleep_interval:    Minimum number of seconds to sleep before each download.
-                       Sleep will be for a random interval if --max-sleep-interval is also passed.
-    max_sleep_interval:Max number of seconds to sleep before each download.
-                       Sleep will be for a random interval if passed along with --min-sleep-interval
-                       or --sleep-interval, otherwise ignored.
+    sleep_interval:    Number of seconds to sleep before each download when
+                       used alone or a lower bound of a range for randomized
+                       sleep before each download (minimum possible number
+                       of seconds to sleep) when used along with
+                       max_sleep_interval.
+    max_sleep_interval:Upper bound of a range for randomized sleep before each
+                       download (maximum possible number of seconds to sleep).
+                       Must only be used along with sleep_interval.
+                       Actual sleep time will be a random float from range
+                       [sleep_interval; max_sleep_interval].
     listformats:       Print an overview of available video formats and exit.
     list_thumbnails:   Print a table of all thumbnails and exit.
     match_filter:      A function that gets called with the info_dict of

youtube_dl/options.py

@@ -501,15 +501,18 @@ def parseOpts(overrideArguments=None):
     workarounds.add_option(
         '--sleep-interval', '--min-sleep-interval', metavar='SECONDS',
         dest='sleep_interval', type=float,
-        help='Minimum number of seconds to sleep before each download. Sleep will be for a random interval if '
-             '--max-sleep-interval is also passed.'
-    )
+        help=(
+            'Number of seconds to sleep before each download when used alone '
+            'or a lower bound of a range for randomized sleep before each download '
+            '(minimum possible number of seconds to sleep) when used along with '
+            '--max-sleep-interval.'))
     workarounds.add_option(
         '--max-sleep-interval', metavar='SECONDS',
         dest='max_sleep_interval', type=float,
-        help='Max number of seconds to sleep before each download. Sleep will be for a random interval if passed'
-             ' along with --min-sleep-interval or --sleep-interval, otherwise ignored.'
-    )
+        help=(
+            'Upper bound of a range for randomized sleep before each download '
+            '(maximum possible number of seconds to sleep). Must only be used '
+            'along with --min-sleep-interval.'))
 
     verbosity = optparse.OptionGroup(parser, 'Verbosity / Simulation Options')
     verbosity.add_option(