It is useful, just be aware you are a completely different type of archer.
Long range shots are best at groups of enemies (though if you do hit they fell it a lot harder then the dedicated snipers). Tin-Can hunting is very possible with a warbow and bodkin and 10PD.
Cav hunting is a breeze. Unlike being a thrower in which they will veer off, cav will always try and run you down, so time it where you send a nice shot into the horse head and watch that rider slide off into your next shot at your feet (Or if it is a ninja cav wearing little or no armor, just blwo the rider's torso in two).
In battles you must be extremely aware of your team, this will allow you to survive if an enemy archer at long range decides to take notice of you. Keep in mind that since you have so much STR you can take a melee weapon and hit rather hard with it. In strategus though I reccomend ditching melee (and thus all PS) and go pure archer and take three quivers (you will be much more useful to your clan, a melee weapon for an archer is mostly pointless in strategus as you have dedicated melee allies for a reason, so use them.).
Mainly in sieges you will shine, as the enemy comes to you and is always in short range. At 130 wpf I have murderous accuracy when defending seiges as destroying shields, sticking feet and blowing off heads when they walk so slow and nice up ladders/towers is a breeze.
It depends on what role you want.
High wpf builds you can snipe and headshot, high str builds you fear no cav, even elephants (Plated Chargers) can go down with minimal effort if you now what you are doing.
I reccomend though not going above 24, as that allows you to kill most enemies with one shot to the head or two shots to the chest and still retain a respectable wpf and athletics. If you really go for a 30, you best quickly stop following the advice of the majority of "snipers" and re-invent your own tactics.
A 30 str archer is useful, but it is not by any stretch of the imagination a "traditional" archer and thus requires different tactics and completely different target priorities.
Oh, and for the record, I have 10PD so this is personal experience.
