Training chest/tri's

Is there any advantages to training chest and tri’s together as opposed to training them on seperate days. A few years ago everyone was preaching to do things like chest and tri’s/Back and bi’s on seperate days(Like chest/Bi’s, Back/tri’s etc). Now it seems like people are going back to the old Chest/tri, Back/bi split. My workout consists of this:

Am I overtraining my arms? I am kinda thin so I was wondering If I should switch things around to prevent overtraining. Are there any advantages if I was to do a chest/tri, back/bi split instead? I have had a long layoff and wish to start out right. BTW, grow is awesome. I did not believe it could taste so could but I am hooked. Thanks,