Oh, and they tell me I’m 36 for this race season, so in swimming/tri does that make me a young or old swimmer…be gentle…
That’s up to you!
The competition in Triathlons seems to get dramatically tougher in the 40+ age groups…so let’s say you’re young.
You’ve got a deal!
Why not work on holding your stroke together… while swimming fast 
Of course you should always focus on your stroke. That’s true whether you’re doing an all out 20m sprint, a 3km TT or your warm up / cool down but there is some sort of matrix/continuum between the % of your max effort you’re trying to put in, how much you can focus on your stroke and how carefully you can do your stroke. Too fast and a lot of your mental energy is focussed on hurting / going fast (even as you focus on the individual bits of technique required to achive this), your stroke is happening quickly so it is hard to get everything perfect and you run out of steam quickly. Too slow and you can’t even swim with proper technique.
The sort of moderate set I’m talking about most of your focus is on technique (I’d like to repeat that you can’t swim good technique if you’re going to slowly) and everything is done at a pace where you can feel each muscle activating, feel the stretch in your lat as you extend out in front (careful not to extend too far or you’ll drop your elbow but at the same time you want to constantly extend your lmiits), feel the grab when you initiate your catch etc (I PM’d Plainsman a little list of things I work on).
I found that when I did less “hard” training and more moderate training working my length etc I got a lot faster. I’m not suggesting that there’s not a place for sets like your 8x300s, obviously there is. I just think that all swimmers and triathletes will benefit from dialing back the pace some sessions and really focusing on relaxed strong swimmming, stretching out their muscles, in particular trying to get their catch as far forward as possible whilst keeping it strong, and generally getting everything spot on.
After all, triathletes are training to compete while keeping their pulse down, so does it make more sense to do all your training with a highly elevated pulse, or does it make sense to do some training in the zone you want?
Personally, I don’t bother doing any other session (I just do variations with toys (dragging a sponge anyone?)). I feel that I get more benefit from moderate sessions and there’s less chance of jumping in, trying to go fast and hurting my shoulders that no longer have the supporting muscles they once did. And besides, why hurt during training if you can put it off until race day? Hahaha - regrettably this does not apply to cycling or running 
True Torres is a sprinter but I bet she or any other sprint swimmer would beat any triathlete out of the water. Even more so over the 500m plainsman is talking about.
Finally - found this truly excellent link in another post - http://www.virtual-swim.com/3d_mv/top_btn/free/2000wc_1500/2000wc_1500_q.html
Plainsman - click on slow motion or stop motion and check out the catch side on and front on. In particular, if you look side on at the catch you’ll note the sharp down movement with the hand/wrist/forearmwhich which initiates the catch while the upper arm / elbow stays pointing straight forward. It’s pretty much impossible to overemphasise this phase of the stroke and in my opinion it is the key difference between elite swimmers and casual swimmers. Casual swimmers generally either bring in this bend too late and miss the front half of the catch or they miss it entirely.