I think you have to assess "the risk" on at least two levels.
As a risk to Mr. Keiser's financial well being, buying the Bandon Dunes property and attempting to develop the first golf course there was not a great or even significant risk.
But, as Adrian Stiff has pointed out, the type of golf resort Mr. Keiser envisioned for Bandon Dunes (firm & fast links-y golf in a remote location, walking only, modest accommodations) was a big risk at the time, when the vast majority of golf resorts were lush and plush. Hiring then unknown David Kidd to design the first course was also a risk of sorts, as most other golf resorts were hiring the "big name" GCA's to generate publicity and visibility for their projects.
As I understand it, Mr. Keiser mitigated the risk by moving slowly, acquiring more property over time, developing one golf course at a time and building out the lodging facilities as demand expanded.