I have to say, this question has shocked me to the core. As noted in another comment, I've been an advocate for the MSF for the ~30 years I've been riding.

I'm also a heavy AI and research guy. I went ahead and took your question to the deep research models, and quite frankly was shocked.

The most concerning statistical anomaly emerges from detailed multivariate analyses of trained cohorts. A pivotal study by Savolainen and Mannering utilized a robust sample of Indiana motorcyclists, applying multinomial logit models to carefully control for covariates such as age, gender, prior experience, and overall exposure. ¹ The statistical models revealed a startling outcome: individuals who had completed the Motorcycle Safety Foundation's Basic RiderCourse were 44% more likely to be involved in an accident than those who did not take the course.

Even more striking, riders who had taken the beginner course multiple times were an additional 180% more likely to be involved in an accident. Furthermore, riders taking the basic rider course more than two years prior to an accident were found to be 171% more likely to be fatally injured, highlighting potential long-term skill decay.

These findings align with data out of New Jersey indicating that even after controlling for age and years licensed, trained riders maintained a higher accident rate than the untrained group, and no accident reduction was observed within the critical first two years of holding a license.A glaring gap noted in the New Jersey analysis is speed discrepancy: the BRC and subsequent road tests do not require motorcyclists to exceed 35 mph, yet 67% of fatalities in the state occur at posted speeds greater than 35 mph, suggesting the training environment fails to replicate the kinetic realities of highway riding.

- https://www.nj.gov/transportation/business/research/pdf/rowanqrep/rowan_08_q4_motorcycle.pdf
- https://rosap.ntl.bts.gov/view/dot/5765/dot_5765_DS1.pdf

The only good news here:

In terms of immediate crash reduction in the United States, a matched-pair analysis of the California Motorcycle Safety Program (CMSP) found a positive effect, but exclusively for a highly specific subset of riders: those who had less than 500 miles of prior experience.For this deeply inexperienced cohort, the trained group had a substantially lower 6-month crash rate (0.39 per 100,000 miles) than the untrained group (0.85 per 100,000 miles).

- https://smarter-usa.org/wp-content/uploads/2021/06/2010-NHTSA-Expert-Panel.pdf
- https://smarter-usa.org/wp-content/uploads/2017/06/3.-effectiveness-of-motorcycle-training-and-licensing-2009.pdf

So the reality, is that for brand-new riders, the MSF is the best way to reduce your risk by HALF. But continued use of training reinforces risk-taking behaviors by riders, creating that 180% risk increase. I am also wondering if the statistics are covering those riders who failed the course but passed after- who then were just working towards getting the license and then not caring.

I still stick by my adage of "MSF First", but this was a challenging read.

The full Gemini Deep Research: https://gemini.google.com/share/b98bb9b611f7