Changing tempo markers universally?

[Tweakhead]

ok. I think this might fix it.
you probably created your tempo map with Beat Detective originally, right?
I noticed that your tempo markers are blue, rather than green.

well, try this . . .
click on the little plus symbol at the edge of your tempo timeline ruler . . .
does it have "Snap To Bar" checked ? or un-checked ?
whatever it is on, select the opposite. click OK.
do all the tempo markers turn from blue to green?
if so, trimming your tempo events should work now.
fingers crossed !

[TWR100]

I'm goin to try this latter and I'll update.

I created the tempo map using the tab to transient and identify beat method. I'm sure you are aware of it.

I don't find Beat Detective as useful for tempo mapping.

[TWR100]

Great!!!

Once I un-checked Snap To Bar I could then manipulate the tempo markers collectively.

One last question. In your opinion, once I have the correct tempo, should I then re-check the Snap To Bar option? I have no idea how this option (checked or not) will effect the rest of the production.

I guess I could find it in the Reference Guide but usually that offers no practical advise.

Thanks again Tweakhead, I doubt I would ever have worked this out for myself.

[Tweakhead]

yes, mine is usually engaged.
I rarely use Beat Detective either these days. I prefer my own sample accurate ID'ing of points. Once fully mapped, it seems sensible for the tempo changes to be happening dead on the Bar, unless there's a deliberate accelerando etc on beats.
I'm glad this worked out for you. It was an educational process for me too, to track down the cause. The screenshots helped immensely. Well done for your perseverance !