I will explain it again:
Grinding = doing the same thing over and over again. Making Gravel into Flint by shoveling it is grinding.
Time Consuming = thinking before doing. Making Gravel to Flint using the previously crafted Macerator is time consuming.
Adventure = finding things by searching intelligently (and luck), this can be shortened to an x*log(n) Effort if done a smart way, and an in worst case an n³ Effort if done stupidly (Quarries are n³ btw.)
So every minute of swinging a pickaxe is Grinding. Its repetitive, doing the same thing over and over.
But a quarry, if done right, creates less grinding than hand mining. (I agree something like a redpower frame quarry is much more interesting than a BC quarry).
IMO the challenge of a quarry is that it sends lots of blocks to your base. If you NEED all of those blocks (like sending cobble to the recyclers) then you need to set up a pipe system to sort it all, get the right ores to the right machines, etc. If you are quarrying a lot and using GT machines to process (at least in older versions) then your cycle time is slow, and your energy use is high, so you need lots of infrastructure to process all of the stuff coming in. Quarries also require infrastructure. If you get rid of tesseracts and ender chests, you have to send the stuff to your base with mine carts.
IMO this is what frustrates me with the 'hard core' crowd. To get away from being swamped in resources from quarries, they play the game with hand mining only. But then it requires no real infrastructure to process it all. Some chests, hoppers, done. Put your backpack of ores into a chest to process, etc.
When you are running 4 quarries at once, stuff is coming in fast. It creates bottlenecks, requires lots of power. I remember running 25 turtles round the clock in 1.4, processing it all with GT machines, etc. It required MUCH more thought and preparation than 'dump backpack of ores into chest connected to a hopper'. It also meant I had to get much more power than i would with just hand mining.
This is why in the pack blockmaster and I made, you only get about 30% of the ores from a quarry than you do in a typical ftb pack. Now yu have the challenge of infrastructure, plus the logistics of moving the stuff home, but hopefully not the overabundant resources.
This was why I jumped into GT so hard in 1.4, needing so much redstone for chrome meant I had a need to keep running auto miners of some sort.
I do agree though that the main community is dead wrong about GT. Mods like Thermal Expansion are the truly 'tedious' mods. Setting up a TE system is no harder than making gravel into flint by shoveling it. Gt requires much mroe thought. Although the ic2 e-net is really what has always drawn me to ic2. I have yet to make any of the mid to high end 1.7 gt machines though, im eager to see what has changed, based off of what people here have said.