We have found there is far more error to be found in sample selection than in anything the laboratory can do.
Example: in our area, the oldest abalone shell has been dated at 5910 BP, while the oldest mussel shell is 9420 BP. The lndians started using mussels early, and abalones, which take a lot more work, much later. If you date only abalone shells you miss out on the earliest 3,500 years of our prehistory.
Another example: some archaeologists are still using multiple pieces of shell in their dates. In any site that has gophers or squirrels, that almost certainly guarantees an error. We dated one site, using single pieces of shell, and found that they were completely randomized with respect to depth. But those single pieces, even though they had been moved around, still gave good dates. Including a large number of shell fragments in your sample will completely homogenize your date: if you have a two component site, Early and Late, that's a good way to get Middle Period dates even though the site wasn't occupied at that time.
A really sneaky one: changing populations and patterns of exploitation over time resulted in early mussel shells generally being pretty thick and robust, but shells from later in time were thinner. This reflects over-exploitation of the mussel beds where the mussels aren't given a chance to grow up. For a while in trying to date one site we were selecting just the nice thick shells, and we kept getting Early Period dates. Only when we selected thin shells did we get more recent dates.
Given all of these sources of bias, and a few others, we don't worry so much about what the laboratory does. We worry far more about what we and other archaeologists are doing!
Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.
Belief gets in the way of learning--Robert A. Heinlein
How can I possibly put a new idea into your heads, if I do not first remove your delusions?--Robert A. Heinlein
It's not what we don't know that hurts, it's what we know that ain't so--Will Rogers
If I am entitled to something, someone else is obliged to pay--Jerry Pournelle
If a religion's teachings are true, then it should have nothing to fear from science...--dwise1