The only way for BFC-certified transparent parts to look consistent with non BFC-certified transparent parts is if BFC is disabled during all transparent part drawing, so I chose to do that. Of course, I added BFC support to LDView over 6 and a half years ago, and there were a lot fewer BFC-certified parts then.
Whether or not it is "wanted" is anybody's guess, but I've never had anyone complain that LDView's transparency was too opaque. However, LDView does cheat on this a bit. The default alpha value (from ldconfig) is 128, and this gets mapped to 110 in LDView. Everything below 128 is interpolated such that 0-128 maps linearly from 0-110. Everything above is interpolated such that 128-255 maps linearly from 110-255.
Note that I chose the 110 value via empirical testing (with two-sided transparent surfaces) before having ldconfig.ldr support, so the mapping was my solution to 128 being the standard alpha for transparent parts in ldconfig.ldr.
Whether or not it is "wanted" is anybody's guess, but I've never had anyone complain that LDView's transparency was too opaque. However, LDView does cheat on this a bit. The default alpha value (from ldconfig) is 128, and this gets mapped to 110 in LDView. Everything below 128 is interpolated such that 0-128 maps linearly from 0-110. Everything above is interpolated such that 128-255 maps linearly from 110-255.
Note that I chose the 110 value via empirical testing (with two-sided transparent surfaces) before having ldconfig.ldr support, so the mapping was my solution to 128 being the standard alpha for transparent parts in ldconfig.ldr.