In brief...
what age you started a routine:
About 17 months with DS, and birth with DD. Should have done it far sooner with DS!
and how strict are you to that routine?
I was very, very strict once I did it. Less so now they're 6 and 8, but they still have set bedtime and routine to go with it. Nap time was always the same for DD; DS used to have to go up to play in his room for an hour once he stopped daytime naps (which he did the week DD was born).
DD (younger) still goes to bed half an hour before DS. I think he needs some one-to-one time with me to mark out the fact that he's older (otherwise I'm tempted to treat them as twins).
Also how strict? Ie: if your going out with the kids do you ensure your home in time to do the routine or not?
I did when they were younger. I tried not to go out if it meant losing our routine. I worry about it much less now. DS only sleeps for about 8 hours anyway, and the occasional late night doesn't harm DD.
I was very strict about the routine when they were little, partly because I needed a guaranteed long hour period when I knew I wasn't going to see them at all unless they were ill. I felt that being with them for 13 waking hours per day was more than enough for them and me! I felt that much more once I had two. With DS, I was so besotted that I was quite happy to stand and stare at him at midnight.
Routine when they were little was bath, bottle, story, teeth, bed with all lights out. Now DS has very long school days, music practice etc, so it's now shower, teeth, reading on his own in bed (he won't let me read to him any more). DD's routine is the same as when she was a baby, minus the bottle!
Sorry again and thanks to anyone who answers.