Structuring training programs off of pre-set percentages has it’s advantages and disadvantages.
For some it provides accountability, structure, a sense of built-in auto-regulation, and I’m pretty sure I read somewhere it increases the likelihood members of the opposite sex1 will want to hang out with you by 413%.
Don’t argue, it’s science.
For others, percentage based training can be a double-edged sword: with loading parameters either too easy or too aggressive for some.
In my latest article over on T-Nation I break things down and and discuss why percentage based training may (or may not) be a good fit for you.