No I really couldn't. The only time I've ever put any weight on is post a weekend session where I'd lost a stone or so and I'm putting it back.
I combine the 2 and have a large meal..Can be anything.. Then i take my bait to work. Todays is sausage/onion rolls, a bit of fruit and several choc bars, and a couple bags of crisps...Then will have a large meal tonight when finished. Plus an unhealthy amount of coffee in the mornings, no sugar.
Yeah worded that badly maybe, point being I couldn't get above my normal weight and I'll only put weight on if I've already lost it.
4 weetabix in the morning. Either sandwiches (4-6 slices) or pasta for lunch. Dinner changes day to day, will mostly contain some form of meat and spuds/a potato product though. I saw a dietitian about it years ago and even on one of their plans I barely put on a pound in weeks.
Perhaps, give it a go. A guy I used to go to the gym with sounds like you tbf. He was pretty tall (probably about 6'2/3) and naturally very skinny. Was obsessed by gaining weight so spent ages doing trial and error on what he needed a day to be eating enough to do that. Worked out at something ridiculous like 6000 calories iirc. He figured it out though and managed to put on a fair bit of muscle weight by doing it, guy was constantly eating though. It is possible for anyone to gain/lose weight but if you are unlucky enough to be towards the end of the scale either way it takes a lot of work. Likewise if you start putting on a load of weight and want to keep it there you have to keep eating the same amounts otherwise you revert back to your "normal", and eating that amount every day is not fun (especially if you are trying to do it in a healthy way).
Got myself pretty fit over the last couple of years through a combination of running and core/cardio work in the gym, generally at least 5times a week. Me, the Mrs and daughter are planning a trekking holiday in the Andes in June so need to keep the fitness levels up as its quite high altitude stuff. Have to try and get the wife sorted as well. She tends to like the idea of adventure holidays but not want to get fit beforehand. I am definitely not carrying her at 5000m.