This is just a theory that I have been thinking about lately.
Many of us are afraid to take days off for fear of loosing current or future gains.
In this same mindset, many of us are constantly coming up with more routines to "SHOCK THE COCK(hereafter referred to as 'SOC')." Because of this, our routines have gotten longer and most of us have sustained injuries due to overzealousness as well as overtraining.
WHAT IF:
What if it were only necessary to PARTIALLY accustom our penises to exercises and that the days off provided necessary time to heal AND a chance for our dicks to go,"phew, I'm glad he's not doing those exercises anymore . . . OUCH! Damn! He's doing them again!" (when we resumed exercises).
i.e. - give our penises just enough time to heal and just enough time to be receptive to the same level of SOC as opposed to having to add an additional hour of exercises each week.
That way we could always experience the "newbie growth effect" that is frequently discussed without having to increase intensity or time excessively to our routines.
Here's my solution: Try different exercises. Practice the ones you like and are effective. Experiment with rest days. Rotate your exercises on a monthly/quarterly basis to continue to SOC without adding significant time to your routines. i.e - Do different exercises, not more exercises.
Concluding note: I personally weightlift and feel my routine is fairly unique and effective. It is unique in that I separate my exercises into different days: Shoulders, Arms, Chest, Back, Leg1, Leg2. I typically work a three day on/ one day off schedule. With this schedule/routine, I end up going anywhere from 4 to 9 days rest between muscle groups! The amazing part of this whole routine is that I gain muscle and strength faster than guys that use steroids - AND I'M A VEGETARIAN TO BOOT!!! I'm also in and out of the gym faster since I am only working a limited muscle group. My whole point is that my routine WORKS. I get fewer injuries than when I used to do a MON/WED/FRI routine working all muscle groups on those days.
While the penis is an organ - not a muscle - I can't help thinking that maybe it could benefit from the same type of schedule as my weighlifting. The difficulty lies in isolating the target areas and the exercises that affect them. Although it would be difficult to work just the tunica without hitting the ligs, it is definitely possible to work on girth without stretching the ligs (ex- basic constrictor).
So, to apply this, one could perform the following basic routine: DAY1 = intense stretching without doing any other girth/width work. DAY2 =constrictors with some minor stretching. DAY3 = stretching and jelqing. DAY4= rest. Repeat.
I'm sure that you see the possiblities with even this basic routine: less time doing routine, retention of SOC factor, adequate rest for growth and perhaps most importantly - the continuing desire/motivation to Penis Enlargement because the routine is shorter and varied.