there is little to no clincal data on the effect of abducted boots. some skiers love them, others hate them, and a large portion that use them can not tell the difference.
in 2007/2008 season nordica took a run at abduction for performance skiers and racers with their 95mm lasted doberman WC 150, 130, and 100 model boots. they also have built a small amount of abduction into their sportmachine models. in 2009/1010 nordica has abandoned the abducted stance at the performance boots and kept it in the sportmachine models.
fischer, on the other hand, has been building abducted boots from it's inception 5 years ago. every boot in fischers line has an abducted stance.
to understand the impact of abducted boots in the U.S. from a marketing perspective, nordica commands over 30 percent of of the U.S. market. fischer would be telling some tall tails if they claimed more than 1% of boots sold in the U.S.
there are so few retailers selling abducted boots, that most of the speculation as to what they do or do not do will be just that, speculation.
so, will abducted boots help with your tired quads? based on the limited information that you have given us, your answer would be more easily solved by writing 10 dfferent possibilities down on sticky notes, tape them to your wall, blindfold yourself, then throw darts at them.
some ideas for you to put on the stickies, would include:
all the basics - proper shell size, proper shell shape for foot containment, good support under the foot, bucklng the boot tight enough, etc.....
alignment of your skeleton over your feet ( canting )
fore- aft balance ( make this one out of a really big sticky note)
assessment of your ankle range of motion in dorsflexion
forward lean of the shell
ramp angle of the boot board
external influences on fore aft balance ( binding delta )
the sun was in my eyes
the dog ate my homework
okay that was a lot of dribble concerning your tired quads and abducted boots. back to your question about abduction. put down the darts and i will address your question.
from a biomechanical perspective, abducted boots will probably not have much impact on your quads. as mtlion suggested, there is probably something else going on with your current set-up or technique that is having a greater impact on your overuse of the quad as a compensator in your skiing. odds are high that it is somethng related to fore-aft balance, however there is also history that shows your problem could come down to simple boot fit issues that can cause tired quads.( for example your heel lifting up off the bootboard everytime you lean forward ) all that being said there still remains an outside chance that for your own biomechanical circumstance, abduction in the boot has an outside chance of being a good solution.
on the personal side, i have been skiing on nordica abducted dobermans for the last 3 seasons, and i love what they do for my skiing. my 13 yo daughter ski races on the fischer abducted jr race model and is having a great start to her season after the switch. in my opinion the benefits of abduction are in most cases improved performance related to on snow behavior and control over the ski. in some cases, for some biomechanical needs, i have seen the abducted boots help solve fit and comfort issues. the problem with making a blanket statement about the pros or cons of abduction in a public forum is the lack of data, and the complex nature of the biomechanics of indvidual humans.
so could abducted boots help your situation? maybe. could there be a whole laundry list of other things that could also make improvement in your comfort and performance? absolutely!!
find a good bootfitter that can eliminate the variables in the set-up that you are currently skiing on. if that does not work, go ahead and throw down for a boot with an abducted stance, what have you got to lose? just make sure that whatever abducted boot you end up in fits well and is a good match for the shape of your foot.