Hey bud. Okay dokay, where to start?
1. Parallel (PTIP) vs taper tip (TTIP): This basically just refers to the two "types" of shafts that can be put into an iron. I am NOT referring to the shaft composition (ie. steel or graphite). Here is the difference between the two:
- Parallel Tip: .370 tip diameter and the weight distribution in the shaft gets lower as you get closer to the hosel (where the clubhead is)
- Taper Tip: .355 tip diameter and the weight distribution in the shaft is even throughout
- SUMMARY: The tip diameters shouldn't concern you. This should only matter if, one day, you end up breaking your shaft, for example. If you decide to buy a shaft from a local golf store and get them to slap it in, you basically just need to make sure that the tip diameter fits and is of correct size. FYI, tip diameter is also quite important in driver shafts too. Some drivers come with .335 tip diameters and some come with a .350 tip diameter. IN TERMS OF HOW THE TWO FEEL (PTIP vs TTIP), I personally cannot feel a difference. I do NOT believe that a PTIP shaft plays differently from a TTIP shaft. The tip diameter and weight distribution SHOULD NOT make a difference. You might ask, then, why companies even bother making two different type of iron shafts. It is only because it ends up being a manufacturing choice. The TTIP shafts are entirely captured by the hosel, unlike PTIP.
2. TT Dynamic Gold vs TT Dynalite Gold XP: Have I ever told you that Titleist is my favorite brand? Great clubs and on top of that, a great website! URL: http://media.titleist.com/images/titleist/pdfs/US/2012/flipbook/Fall_2012_Custom_Club_Options/html/index.html
The reason why I gave you that link because many of your golf shaft-related questions can be answered here! For example, go to page 10.
- Dynamic Gold: S300 = stiff flex, 127-130 g, low launching shaft
- Dynalite Gold XP: (let's assume S300 for comparison's sake) = stiff flex, 117 g, mid-launching shaft
Which should you choose? Depends on your ball flight. Personally, if you are carrying the ball over 154 yards with a 7-iron, I would go the Dynamic Gold. High ball flights are a common problem that I see with customers at work when I do golf fittings. I prefer lower launching shafts. They are heavier, but since you hit a 7-iron moderately deep, you should be ok. Food for thought: I guess the website doesn't have it, but I would consider an R400 over an S300. I ALWAYS ADVOCATE for regular flex. It is far more forgiving and with your handicap, a heavier R flex shaft is better than a heavy, less forgiving S flex shaft. I currently play Titleist 712 AP1 irons with R300 Dynalite Gold XPs. Decent shafts, but they launch a little too high for me. I plan on switching to AP2 irons with R+ flex KBS C-Tapers. Again, I prefer the R flex lower-launching shafts, but that's just me! :-)
P.S. Some iron shafts do have unique properties between PTIP and TTIP. For example, KBS C-Taper shafts come R, S, X in PTIP, but for TTIP, they come in R, R+ (between R and S), S, S+ etc. So, sometimes knowing what kind of tip your irons are allows you to have more options to choose from for shafts!
Good luck once again! I better stop babbling now ;-)