I know that if a single client performs some order
operation, such as changing the price, then it must
wait 1 second before attempting another operation
on the same order.

But I was wondering, what if 2 API Strategy clients modify
order price, and they are not coordinated in any
way, such that A modifies, then B happens to
modify the same order, within the one second
mandatory delay.

Will this throw an exception for Strategy client
B ?

In other words, is the timing enforced by the
server, or in the API client, on a per-client
basis?

The reason I'm asking this is that I have a
customer who introduced a secondary Strategy
which modifies orders. If these modifications
happen to fall within the one second window,
then that would introduce errors, conflicting
with the primary strategy's order operations.

Thanks for clarifying this,
HyperScalper

To be precise - not "another operation", but the "another operation of the same kind".
No.