after eschewing a scale for a while in favor of a scoop i am back to weighing beans after the quality of my pulls unaccountably crapped out. after several months of very satisfying consistency, the quality of my pulls unaccountably turned south with thin, fast cups. while i have yet to prove this, i suspect the issue is the much lower weight of beans in my wood heated house now that it is winter. i just weighed my standard double espresso measure and it came in at a measly 13 grams.
i'm not sure this is the issue but if it is, this is perplexing. one would not think that water weight by itself would change the quality of the espresso. i would have expected the opposite, that bean volume was the key dimension to measure.
Steve

Was the mashed volume lower than you remember?

With more static due to lower humidity, depending on 101 variables, the density can decrease.
Once mashed, the volume should be similar year round.

important followup: my problem turned out to be a broken burr set on my virtuoso, not changes in humidity. i fooled myself into thinking that tighter grind would make the difference and it did, only briefly. ditto messing with the dose. when nothing seemed to work i took the grinder apart and found one of the tabs broken off the upper burr holder.
so now i am grinding with my faithful turkish mill, which is thoroughly dialed in and consistent. and i am measuring beans again with my new 0.1 scale, and i am back in the money, as they say.
Steve

Sorry to hear about your burrs....

But a scale is never a bad investment

two of the three tabs remain, enough to keep the burrs more or less aligned but not enough to enable them to grind finely or consistently. no abnormal noises, though.
one positive result is i am finding i can make wonderful consistent espresso with my hand mill(zass turkish mill), leading me to wonder, if i am only making 1-2 pulls per day, why bother with an expensive electric machine?
Steve