I drew most of my HR stuff from the Ride skill itself, extrapolating somewhat.
{and having re-read it last night, you may notice some differences in what I post here and what is upthread...}
Key points:
- Ride check required if the mount executes an unexpected move {rear, bolt, etc}
- Ride check as a move action to control an untrained mount, failure wastes the entire round
- Full round actions limited to Ranged weapons and spells. Attack occurs at the mid-point of the mounts travel
- Melee attacks limited to a standard action
- Riding a controlled mount matches intiatives between rider and mount, the pair then shares move actions to some degree.
So, riding an uncontrolled mount...which is not directly addressed in the SRD..
- Mount is always executing unexpected moves
- Rider would have to coordinate timing to match actions in combat.
Simplest answer to these points would be:
- Require a Ride check to hang on each round. Extrapolating a bit from the key points above, as you are just hanging on, not attempting to control, use a free action Ride check to hang on, failure wastes a move action.
- Rider must use Ready actions if he/she wishes to act at some point during the mounts movement.
IMO this is as close to the RAW as we can get.. as this subject is one of the most poorly and most often used {or more correctly ignored} aspect of the rules.
An appropriate saddle would provide a slight bonus to the ride checks, but not negate the need for them. {altho a high enough skill would make actually rolling the check pointless

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