"Continuous" handles?

OK, so I scored a big sheet of 3/4 exterior ply at the BORG for 70% off, and I needed to build some boxes, perfect. Normally I cut all the pcs first, then cut the handles, then finish the assembly with Titebond III and staples. But, I have found that cutting the handles using the jig I built like another member here suggested (using a circular saw and an angle plate, nibbling away at the shape until the handle is cut) takes a huge amount of time, and my back isn't happy with me afterward. Considering that I've got parts on the bench for 6 boxes, I didn't feel like spending more than an hour hunched over the bench to put handles on 24 sides. So, while I already had the dado blade in the saw to cut the top frame rests, I just dropped the 3/4 wide dado set 1/2 way down the side and cut another dado all the way across the OUTSIDE of each part. This creates a "notch" all the way around, essentially giving me a way to grip it however I want. The only potential issues I can see are that such a cut weakens the box by taking away nearly 50% of the compressive strength, eliminates 50% of the insulating value in the strip right around the middle, and perhaps gives other insects like ants and spiders another place to hide.

Bottom line, has anybody else tried this? Any issues? It'll save a ton of time, and simplify the build process further. Using ply with lap joints, and "continuous" handles, I could probably kick out an entire set of boxes from the whole sheet in less than an hour