If so, explore your cable modem and see if it's possible to manually configure the link speed to 100 Mbps (leave duplex set to auto-negotiation, though). This should cause your link to always auto-negotiate to 100/full and, at that point, bufferbloat (in that direction, at least) should (in theory) be much less of an issue (or potentially even non-existent!).
Unfortunately, some cable modems have very few configuration options that can be controlled or modified by the end user (they download their configurstions via TFTP at startup, as you probably know) -- especially when it comes to ISP-provided (or, worse, "ISP-customized") cable modems.
You're correct. Even though I have a decent third-party modem that I own, it lacks any real configurablity because most of the options get locked away by TWC.
If so, explore your cable modem and see if it's possible to manually configure the link speed to 100 Mbps (leave duplex set to auto-negotiation, though). This should cause your link to always auto-negotiate to 100/full and, at that point, bufferbloat (in that direction, at least) should (in theory) be much less of an issue (or potentially even non-existent!).
Unfortunately, some cable modems have very few configuration options that can be controlled or modified by the end user (they download their configurstions via TFTP at startup, as you probably know) -- especially when it comes to ISP-provided (or, worse, "ISP-customized") cable modems.