Yeah if you really want to gain weight and your coach wants you to gain weight then there are 1.5 options for you:
1] ask your coach for some "non OL day" training days for you. He may or may not give you some extra training days.
1.5] You remodel your training scheme because it's less-than-optimal. you want to be a bad ass gentleman OLer? gain weight as such. something like the following [rough and loose and untailored to your specific needs of course] might [will] be better:
Back squat: 5x10
Chin up [clean/jerk grip]: 5x7
Snatch pull from boxes/rack [bar at mid-thigh] with full shrug: 7x5 [1-3s pause between reps]
Front squat 7x4 [dont do high reps on these. almost everyones upper back looks like shit after rep 5]
horizontal row of some kind: 5x10
Back ext/GHR: 5x10
Overhead Squat: 7x5
Overhead press: 8x8
DB row: 6x5
Sun: Eat triple your regular calories.
If the OL is mostly technical work then you need to gain weight in the important areas. fuck chest lifts. Not worth a shit in OL. Squat my friend. Once your ass is so big people accuse you of riding an ostrich around you will have an easier time with heavy lifts.
OL training always included some heavy squats in my past experience. But I suppose right now my current "coach" isnt really squatting me for shit or lifting me for shit so I feel your need to aux train.
But ideally you should talk this over with your coach and if he is worth a shit he will likely give you some training that will be tailored to his needs for you. If he's like my current coach then he'll tell you to never train hard so you never get injured. You will also take a million years to succeed or not at all but apparently thats ok over here. /end rant/pity party
focus your efforts, sir.
Trust me man most of my weight(not much) is in my legs and ass. I LOVE LOVE squatting. My coach is pretty awesome, at this point he says he doesn't want me to get to sore from the workouts sense he's teaching mostly technique and I guess he doesn't want me to start putting up heavy weight without drilling the tech down.
Last Saturday though I asked if I could try my one rep max on back-squats. I've never had spotters before so this was the first time doing a one rep max, it was pretty awesome to say the least. I also did some doubles and triples.
Yeah, but there is Zero sense in doing horizontal pressing lifts. And that is coming from a huge advocate of cross training for your OL performance.
Put you body through range of motion that it will encounter in the lifts. Overhead pressing, push pressing, Squatting, above knee pulls. That should be your extra lifts.
And only do one squat variety in any one day. And If i were you I would being with heavier volume sets such as 8 or 10 reps in the very beginning. It will help you gain weight faster. I could put on about 1.5kg lean during the months where the squats got volumey as in +5 reps.