- * Update snd_mss to reflect the effective segment size that we can send
- * by taking into account all TCP options, including SACKs
+ * Update burst send vars
+ *
+ * - Updates snd_mss to reflect the effective segment size that we can send
+ * by taking into account all TCP options, including SACKs.
+ * - Cache 'on the wire' options for reuse
+ * - Updates receive window which can be reused for a burst.
+ *
+ * This should *only* be called when doing bursts