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Stack System Program 6 is done. My final training session was March 16, 2026. My official progress check-in — where the Stack app locks in your end speed — was March 22. Fifteen months after I swung a Stack club for the first time in December 2024.
The headline number: I started Program 6 at 105 mph and finished at 106 mph. One mile per hour of driver speed gain. If you were expecting a dramatic reveal, this isn’t that article. But if you want to understand what actually happens when a 56-year-old sticks with an overspeed protocol through six programs and 15 months, keep reading.
The Full Journey First
Before I break down Program 6 specifically, it’s worth zooming out. When I started the Stack System in December 2024, my driver speed was 89 mph. I was a 7 handicap at the time. I’m a 3 now. That didn’t happen by accident.
Here’s every program checkpoint:
- Foundation (completed Feb 22, 2025): 89 → 94 mph (+5)
- Program 2 (May 11, 2025): 94 → 99 mph (+5)
- Program 3 (May 12, 2025): 99 → 99 mph (0)
- Program 4 (Jul 27, 2025): 99 → 101 mph (+2)
- Program 5 (Oct 21, 2025): 101 → 106 mph (+5)
- Program 5 recheck (Dec 31, 2025): 105 mph
- Program 6 (final session Mar 16 / progress check Mar 22, 2026): 105 → 106 mph (+1)
Total: 17 mph gained over 15 months. At 56.
For the complete breakdown of every program’s data — weights, eSpeed charts, and personal bests — read my full Stack System swing speed results.
The gains were never linear. Program 3 produced nothing. Program 4 produced 2 mph. Program 5 was the best single program of the entire run, adding 5 mph. Program 6 added 1. That’s how speed development actually works — you’re not going to PR every cycle, and anyone telling you otherwise is selling you something.
Every program, including this one, was assigned by the Stack algorithm. The recommended protocol all six times: Full Speed Spectrum.
Stack System Program 6 by the Numbers
Program 6 ran from early January through March 16, 2026, with the official progress check-in on March 22. The Stack protocol separates the final training session from the speed test — you complete the program first, then check in fresh. Here’s the full baseline vs. final breakdown across every weight:
| Weight | Baseline (Jan 2) | Final (Mar 22) | Change |
|---|---|---|---|
| Driver | 105 mph | 106 mph | +1 |
| 280g | 91 mph | 89 mph | -2 |
| 195g | 100 mph | 98 mph | -2 |
| 145g | 102 mph | 104 mph | +2 |
| 95g | 107 mph | 108 mph | +1 |
| 0g Trail | 104 mph | 110 mph | +6 |
| 0g Lead | 99 mph | 101 mph | +2 |
A few things worth noting here. The heavier weights (195g, 280g) showed slight declines from baseline to final. I wouldn’t read too much into that — those numbers fluctuate based on fatigue state and how warmed up I am. The 0g Trail jump of +6 mph is the standout. That number represents unloaded swing speed, and 110 mph there is meaningful context for where my nervous system ceiling is sitting right now.
Stack System Program 6 eSpeed Data
The Stack app tracks eSpeed — a projected driver speed based on your weighted training swings. Across 24 sessions in Program 6, eSpeed ranged from 101 to 107 mph, ending the program at 106. That range tells the real story: my system is capable of 107 under good conditions. The final check-in landed at 106.
Stack System Program 6 Session Stats
- 24 sessions completed
- 141 swings logged at the 195g benchmark weight
- Grit Score: 22 of 24 sessions at 100%, two sessions at 98–99%
- Health & Energy: 100% most sessions, dipped to 80% on sessions 8 and 23
The Grit Score is the Stack app’s metric for session completion and max-effort compliance. 22 out of 24 at 100% means I showed up and went hard almost every single time.
The two sessions where Health & Energy dropped to 80% — that was the beginning of my plantar fasciitis. It hurt. I picked up a pair of PowerStep Pinnacle Insoles and just ground through it. I logged the honest number in the app and kept going. That’s what the Grit Score is actually measuring.
Distance Potential
The app also calculates Distance Potential — an estimated carry based on eSpeed at a normalized temperature and altitude. Program 6 peaked at 288 yards, ended at 285 yards (measured at 70°F, 0 ft elevation). For context, that’s the theoretical ceiling under ideal conditions. On the course, real numbers depend on strike, launch angle, spin, and what Southern California decides to do with the weather.
The @115at56 Goal: Where Things Actually Stand
My brand goal — the one that names the site — is 115 mph driver speed before or at age 56. I turn 57 in December 2026.
I haven’t hit 115 with a driver. My driver best is 106 mph.
But here’s what happened during Program 6 that I didn’t expect: on March 6, swinging an 80g weight — one step up from the lightest training weight — I hit 115 mph. That’s the @115at56 goal weight. My nervous system has accessed that speed. The question is whether the driver catches up to the lighter weights, and how much runway I have.
The lightest weight personal bests as of the end of Program 6:
- 60g: 114 mph (Feb 22)
- 65g: 113 mph (Feb 8)
- 75g: 113 mph (Feb 27)
- 80g: 115 mph (Mar 6)
- 95g: 111 mph (Mar 2)
There’s clearly speed in there. The gap between 80g at 115 and the driver at 106 is real, and that gap doesn’t close automatically. But the pattern across this training block tells me the ceiling is higher than what’s showing up at driver weight right now.
What Stack System Program 6 Actually Proved
Program 6 wasn’t a breakthrough. It was a consolidation.
After the big jump in Program 5 — which took me from 101 to 106 mph — Program 6 held that speed and extended the personal best range at the lighter training weights. The driver didn’t make a dramatic leap, but the speed shelf extended upward on the light end of the spectrum.
At this stage in a long training cycle, that might be exactly what’s supposed to happen. The heavier weights lag the lighter ones. The driver lags the training speeds. There’s a transfer effect, but it’s not immediate and it’s not guaranteed.
What I can say with confidence: 17 mph of driver speed gain over 15 months, dropping from a 7 to a 3 handicap, consistently competing in SCGA One Day Series events, at age 56, is real. It’s documented. It’s in the app data and it’s on the scorecard.
The @115at56 goal is within reach of the training weights. Whether it translates to the driver before December is what Program 7 is going to answer.
What’s Next
With Stack System Program 6 behind me, I’m moving directly into Program 7 later this week. The Stack algorithm is recommending Full Speed Spectrum again — same protocol I’ve run all six times. I’ll document the baseline numbers when the app sets them, and I’ll continue logging every session in the Speed Log.
If you’re earlier in the Stack journey and wondering what results look like at 15 months, I hope this answers the question more honestly than the marketing does. The Stack System works. It’s not magic and the gains aren’t linear, but 17 mph over 15 months at my age speaks for itself.
Training data sourced from the Stack System app, Full Speed Spectrum protocol. All speed measurements via the Stack radar. Distance Potential calculated at 70°F, 0 ft elevation. Final training session: March 16, 2026. Official progress check-in: March 22, 2026.
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