Resistance training Vs Static stretching

This is only one short study, but it does imply that possibly a decently designed resistance program using full range motion could be as effective as static stretching on flexibility. Many people over the years have noted that a good weight training program can help flexibility, but this is the first direct evidence I've seen. Longer studies on this would be interesting, also seeing if there is a limit beyond which you need stretching, or you get enough flexibility from good strength programming alone?
Also many people do resistance training AND static stretching, so having another group just in case the synergistic action could be greater than either done separately?

Quote :

http://www.ncbi.nlm.nih.gov/pubmed/21969080

J Strength Cond Res. 2011 Dec;25(12):3391-8.
Resistance Training vs. Static Stretching: Effects on Flexibility and Strength.
Morton SK, Whitehead JR, Brinkert RH, Caine DJ.
Source

Department of Physical Education, Exercise Science, and Wellness (PXW), University of North Dakota, Grand Forks, North Dakota.
Abstract

Morton, SK, Whitehead, JR, Brinkert, RH, and Caine, DJ. Resistance training vs. static stretching: Effects on flexibility and strength. J Strength Cond Res 25(12): 3391-3398, 2011-The purpose of this study was to determine how full-range resistance training (RT) affected flexibility and strength compared to static stretching (SS) of the same muscle-joint complexes in untrained adults. Volunteers (n = 25) were randomized to an RT or SS training group. A group of inactive volunteers (n = 12) served as a convenience control group (CON). After pretesting hamstring extension, hip flexion and extension, shoulder extension flexibility, and peak torque of quadriceps and hamstring muscles, subjects completed 5-week SS or RT treatments in which the aim was to stretch or to strength train the same muscle-joint complexes over similar movements and ranges. Posttests of flexibility and strength were then conducted. There was no difference in hamstring flexibility, hip flexion, and hip extension improvement between RT and SS, but both were superior to CON values. There were no differences between groups on shoulder extension flexibility. The RT group was superior to the CON in knee extension peak torque, but there were no differences between groups on knee flexion peak torque. The results of this preliminary study suggest that carefully constructed full-range RT regimens can improve flexibility as well as the typical SS regimens employed in conditioning programs. Because of the potential practical significance of these results to strength and conditioning programs, further studies using true experimental designs, larger sample sizes, and longer training durations should be conducted with the aim of confirming or disproving these results.