Your observation is not a theory. It cannot possibly ever "work" because it's completely meaningless.
There is always some minimal trading range for every stock for the past 30 or 40 or 50 years. When PFE swings only 23% or 22% some year, then that will be the new magic range.
For an investment "theory" to work, it has to be of some practical use. Your observation fails this test miserably. It has not worked 100% of the time, since every prediction you've ever made based upon it has failed disastrously, just as your betters warned you in 2002 that all such range "theories" necessarily must, as you can't know the top or bottom for the year in advance.
Pfizer had only a 23.7% range in 1988 and since then, there has been only one other time (24.1% in 2007) where a 25% range has failed to be seen. There were also 25% or higher ranges in the six years prior to 1988.
Yes - the Theory does indeed work and this will be at least the 30th consecutive year where it has worked. It could easily be much more than that as 1982 is the earliest year that I can readily check.
A theory is not good unless it can be interpreted accurately to provide useful predictions. Obviously this theory cannot:
"Range theory tells me that Pfizer cannot be prevented from busting through $29 resistance before 2008 is out. I'm putting my money, my credibility and my ability to continue posting here on that assertion."
"Cannot be prevented" is a rather definitive and absolute statement.