Divisions or units are marked on the control wheel boss. I have always worked on 1 unit/5kts crosswind.....it works.
Blip
The reason I ask is because my gut feeling is there's more risk to the operation by not puting in enough aileron during a crosswind take-off for fear of spoiler deployment than there is by puting in aileron in proportion to rudder displacement and accepting the extra drag. This risk by under doing the ailerons comes during rotation.
I have seen first hand the 1-2 degrees roll during the take-off run (yes you can see it on the ADI) suddenly become roll of 5 to 10 degrees during rotation because there was insufficient aileron into wind. How we didn't get a pod scrape I do not know.
There are 2 quite conflicting camps of opinion here. I believe you said it above- the drag from a few spoilers on one side slightly uplifted, at the low speeds before rotation, is immaterial. You only have to see how relatively ineffective full spoilers are below 250kts to appreciate that- at far lower take-off roll speeds, it's irrelevant. What is startlingly noticeable is rotating in a strong crosswind with not enough aileron held on! On a 747 7 hour flight, a copilot didn't hold any aileron on in a crosswind- I thought 'I'll let him feel what happens and talk about it later'. Even I wasn't ready for what happened- it was startling. When you do long heavyweight take-offs in a 747, I still think it better to have all the aileron you need until lift-off. I really think the drag is negligible.