I whined and complained wrote about this issue a couple of years ago, and I made some lazy assumptions about gutters that were not borne out when I actually dealt with a professional...somebody who doesn't just talk out of his ass like yours truly.

Contractor-grade gutters are 5" wide, and cannot handle extremely heavy rain, especially the gutters on the lower roofs which have to handle the water coming off the upper roofs.

Sounds like common sense! The gutter guy who came out a few months ago explained that to me, using small words spoken slowly. The gutters he replaced with correctly sized ones are not overflowing today, but the other ones...the contractor-grade ones...are merrily spilling over.

I see another visit from him in my future...