As stated by Moore, Tibetan Buddhism is, in one sense, “a far, far relative to the Buddhism supposedly passed along from the historical Buddha ... ” From another perspective it can be seen as a highly evolved system of Buddhist practices, firmly rooted in the original teachings of Shakyamuni Buddha.
The prayer wheels and gurus should be seen as “skillful means” through which one can experience the true nature of all things. At the end of the day, however, all skillful means must be dropped in order to be completely free. They are not ends in themselves. In addition, a good teacher would not encourage a student to engage in any of these practices if they are not comfortable with them. Furthermore, good teachers that I have encountered spend a good portion of their time dissuading students from “jumping in to fast.”
As far as Ole Nydahl is concerned, I have not personally met with this individual. However, I have heard some people find his sometimes unorthodox approaches to be very useful.
Others are not drawn to his style. Moore’s gut feeling has some truth in it. There can be danger in the practice of transcending the “supposed illusion of ones ego-identity while, in the process, merging one’s self with that of another, supposedly ‘higher’ being.” I did not begin any form of these practices until I had practiced for about 12 years. One can gain a tremendous amount of peace and insight simply by engaging in a simple “following the breath” sitting-mediation practice that is done on a consistent basis.
There also are fairly simple practices that help one cultivate feelings of love and compassion toward others. Sincere and consistent practice in these two areas will provide one with a solid base to perform more advanced practices. Also, while one slowly gains proficiency, one can take the time to do some real homework on your teachers and their lineages.
The Internet can be a great tool. Talking with other seasoned practitioners of prospective teachers can be even better. I personally feel devotional practices such as those cited are very powerful methods that can provide very powerful results.
Unfortunately, those results can be either positive or negative depending upon the aims of both the student and teacher.