Recovery is what I was getting at. If legs are going to tax my body and lead to slowing down PR's in upper body lifts Id rather not do them. But if they wont and will help my upper body in some way I could see myself doing them. Im 5'10, 225lbs and 15% BF. In 3 years of training consistently ive barely trained legs at all. Last cut i decided to train them on a cut in a deficit. In one month my squats went from 185x5 ATG to 345x5 ATG and my legs were in proportion with my upper body. In a month. So basically I see it as, if they ever get too small, I can get them to catch up in a month or two and be in proportion, easy.
I probably had 28" thighs then and could fit into 30 waist jeans. So I had to actually wear 36 waist jeans for my legs to fit. Wasnt too great.