Yes… it would be DETRIMENTAL to add in 2 extra weight lifting sessions assuming your 3 weekly weight sessions are up to par with intensity/ rest periods.
And no, it’s not a stupid question by any stretch. Many sometimes confuse weight loss lifting protocol with “the more the better”. You can get away with this most of the time when you are trying to build muscle and eating loads of calories.
But from a V-Diet point of view, doing 2 extra sessions has no benefit. Why? Because you’re in a calorie deficit. Your body won’t grow much if at all when you’re taking in sub- maintenance calories.
If you think about it, when you work out you are actively breaking down muscle. Your muscles grow when these broken down muscles get the much needed calories they need to do so. When you’re only taking in a thousand or so calories they don’t grow. You are simply lifting 3 days a week to keep these muscles activated, signaling to metabolic and physiologically processes that “Hey these muscles are being stimulated, we better keep them around and not use them for energy (extended cardio/ weight training)”, hence the V-Diet’s capability to preserve lean body mass (as long as you are properly supplemented- Surge, BCAA, protein powder, fish oil)
I am very happy you asked this and didn’t go ahead and assume that working out more would be better or as effective.
Good luck with your training!