"'What's better' is to some degree a matter of personal preference. The general recommendation is that as your exercise intensity and duration increases, your body temperature will increase, so you should dress as if it's five to ten degrees warmer than the starting ambient temperature. Remember that the purpose of layering is twofold: to keep warm, as well as to wick away moisture, so your choice of layering materials is important. Wear a good wicking layer close to your skin with a warmer, but moisture-absorbing layer, above. Your outermost layer should also be wind- and/or climate-resistant with evaporative properties (e.g. ventilation in the armpits/sides). That said, people warm up at different rates and it's not surprising that you may warm up more slowly than your boyfriend due to the difference in muscle mass, among other factors. Shedding layers also leaves you with the problem of what to do with the extra clothes that you're wearing (leaving them by the side of the trail isn't always an option). But the bottom line is to go with what works best for youif you're miserable starting off cold, and if you're OK with packing the shorn layers, you may be less efficient but you'll be out there exercising."
So there you go. I think you need to do whatever makes you most comfortable, and tell your boyfriend to take a hike if he doesn't like it!
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