I made a couple of rash errors during intense scenes early on in our relationship, largely where I've overestimated both my own Domming abilities and the elasticity of pup's limits. It's all very well pushing your sub to the brink, but when it could lead to mental or physical harm if they go over that brink (literally, in one of those two cases), you risk ruining the most important thing in any relationship, let alone a BDSM one: trust.
I'd like to think that I've learnt from these two incidents (touch wood). I will tend to approach a scene with a worst-case scenario in mind. If this means that I turn into a job's-worth health and safety manager, so be it - just hand me a clipboard, a hard hat and a fluorescent tabard. But I'd say we're pretty adventurous. For instance, we have indulged in mild edge play (if that's not an oxymoron). We both find stuff like breath control and noose play an adrenaline rush, but we're only too aware of the dangers and I will always, always, always be on a heightened state of alert and err on the side of caution.
I'm not a natural sadist, but I have learnt to enjoy giving pup a whipping. It's more that I've realised how much she enjoys pain and I've become slightly more adept at giving her the stripes when I desire. Ironically, while pup feels extremely subbie when I zip a hood over her head, then I wear my own balaclava-style latex hood I feel more free to adopt a Domly persona and be rougher with her. Go figure! Up until very recently, she has had a bit of a problem seeing me as the "masked abductor", but pup's latest post about wearing my inflatable hood proves that she has come an enormous way and I am so very proud of her.
pup does want and need to be pushed - there's no doubt about it. I think she needs a CPD (corporal punishment development) plan, don't you? ;-) But seriously, I do recognise that we both need to evolve and, in so doing, strengthen our bond - no pun intended. I know there are Domly things that don't come naturally to me that I should work on and give more consideration.

pup needs to feel submissive for more than just the few precious hours a week that we're playing, which I appreciate totally. She requires that all-round feeling of being owned, which is pretty hard to achieve at the moment. But I am too laid-back a personality to constantly think, speak and act like a Dominant. I acknowledge that this will probably remain an issue to a greater or lesser extent. When it comes down to it, I'm too content with my life (touch wood again) to always feel the need to exert my power over another. And, what's more, there's a lot more to both our lives than BDSM. The vicissitudes of vanilla life tend to be too intrusive to be ignored for long.
Don't get me wrong: I absolutely LOVE domming pup. A good scene is such a turn-on. I get a huge sense of satisfaction when I've given her exactly what she needs and she's lying exhausted and exhilarated in my arms after a real working over, culminating in a shattering orgasm. It can be huge fun for me to sketch out (maybe over the preceding week or more) what I'm going to do with her, especially if I've bought another new piece of kit for us to try. But I'd be a liar if I said every scene goes like that. Sometimes I feel too tired - perhaps lacking energy after a hard week at work - to adopt the role convincingly. Any lack of effort or conviction on my part will show up pretty quickly, and I hate to disappoint pup if I, for instance, fall asleep before we get a chance to play. And here's the heavy weight of responsibility again that I mentioned at the start: while the sub experiences pain, discomfort and humiliation, the pressure is definitely on the Dom to give her the tough time she desires - to produce the goods, to make the plays, to call the shots etc, etc - you get the picture.
In that way, I'd argue it's harder to be the Master. This is why I ask pup to switch once in a blue moon (which, as we all know, is every six months). I don't ask her to go beyond our comfort zones and start going all Chanta Rose on my ass. I'm just asking her to be my assistant. I do it partly to test out a new piece of kit - perhaps it's something she's not sure about and needs to see how it works - and partly to assuage my curiosity about how it feels to be restrained in, say, the inflatable sleepsack (awesome, if you're wondering). I enjoy these rare diversions from the norm, because the duty of care is no longer mine. I can lie back and enjoy the ride - although I normally end up topping from the bottom! I think it shows pup what has to go through the mind of the Dom when they are in the position of full responsibility.
I hope none of this sounds like I'm complaining - far from it. I don't think I've been happier in my life. We have worked to get to a position of strength and I want things to get stronger. As with many things, you get out what you put into a relationship. If that's sometimes an effort, it's an effort worth making.
SingleGlove