What constitutes an undertaking

[the wopster]

Hopefully one of our resident police officers or some might know this answer, What constitutes as undertaking? On my way to work I always try and sit in the inside lane (where possible) of 3 lanes I tend not to go above 60-65mph, am I undertaking if I haven't moved lanes an I go past someone who is sitting in the middle/outside lane that is going slower than I am?
I always understood it to be undertaking if I came up behind someone in the outside lane then moved into the inside lane to go past them and then moved back into the outside lane once I passed them.
Are both classed as undertaking or just the latter?

 

[the wopster]

I define it as going out of your way to pass a vehicle on the left hand side. If you're travelling on a set path (Steady speed in lane 1 of the motorway for example) and you just happen to be passing people to your right, that's not an undertake.

If you're in lane 3 and dive into lane 2 to pass the car infront and back into lane 3 again, that's an undertake.

That's what I though, but it seems to be a bit of a grey area, for instance on my way home I travel down a 2 lane slip road I always choose the inside lane but numerous times I have went past someone that's in the outside lane doing 25-30mph on a 50mph road, I'm not booting it either I tend to do 5-10 mph under the speed limit most of the time

 

[the wopster]

And this is what I mean by gray area, 3 different people with 3 different opinions! You could get a police officer that sees it your way or you could get one that goes by the letter of the law and does you for dangerous/careless driving because you have passed on the left.

 

[the wopster]

So no further forward then lol. it's early afternoon, I'm in lane 1 doing 65-70mph and the motorway is quite except a car in lane 3 doing 65mph am I ok to carry on in the lane I'm in or do I move into lane 3 sit behind him until he pulls over then pass him and move back into lane 1?

 

[the wopster]

I'm pretty sure in that situation the person sitting in the outside lane below the speed limit is going to be the one getting pulled as technically in that situation it would be impeding the flow of traffic.

What about if he's in lane 2 and lane 3 is free? See what I mean about it being a very grey area, everyones opinion and judgement has been different. And I'm guessing a lot of police officers will see it differently also.