Sorry, I just assumed we are talking about a decent players and possible strategy against them. Of course you can hope that someone is leaving 50k clubs at home and that might work some of the times but if your opponent is active enough to send farmlists every 10min and experienced enough to feed such an army then I'd doubt he is gonna leave his rams/cata or army at home. And yes, COM is completely different ballgame than some local servers.
Can you stop with the arrogance for just a moment?
You're not talking to a bunch of newbies and you are not a god at this game. So stop the arrogance please.
There are 2 scenarios:
1. Enemy farms inactives with farmlist and is thus competition to your farming.
If the enemy farms then there will be a moment where he is not online and a portion of his troops have returned home from farming. That is when you can make some nice kills. You'll never catch the entire hammer, you'll always catch something if the enemy is offline. I'd say it is safe to assume 5% of troops to be home when you attack. 5% is pretty nice to catch, you do this a few times and you'll really halt his farming, forcing him to be online more or depend less on farmlists to ensure his returning troops don't get caught.
2. Enemy doesn't farm inactives with farmlist and is thus not competing with you.
If he ain't competing then who cares? Yeah it can be a dangerous hammer but you are unlikely to ever catch a significant portion of their troops during normal attacks (so not including sniping a returning hammer) cause he'll make sure to always be online when his troops are home.
How do I get to 5%?
Well catching (portions of) hammers works best against teuton hammers, which primarily consist of clubs.
Those hammers easily hit the 999 limit for outgoing attacks, meaning they can't send everything away at all times, AND they will have loads of returning troops all the time.
To be honest, you can probably catch a fair bit more than 5% from teutons.
For the other tribes it is a bit different cause these don't hit the 999 limit as soon since they have less troops.
However, these tribes generally pay for their higher offense per crop consumption (swords/imps) or movement speed(cav) while not really gaining much defensive bonus. Meaning you can still catch quite a bit of value when you attack them.
In any case, if they compete with your farming then they will have a portion of troops at home at some point unless they have 24/7 online time due to duals and/or sitters.
Don't try to snipe with walking times longer than 2 hours cause then they have too big of a window to secure their troops.