I've been keyframing animations with Poser for quite a few years now, it's become second nature now. Fortunately, P5 hasn't altered any of the animator's tools so it's relatively simple. The tricky bit comes with dynamic clothing, it's a bit hit and miss there because you can't actually see where the clothing is going to be and a slight alteration can have dramatic effects. One of the secrets is not to go for long animations, keep the scenes short and punchy, I rarely use anything longer than 100 hundred frames tops...