Good reply mso. Anyone doubting that wisdom read what Greg Pease says about smoking Gaslight in a small bowl before loading up that 2" deep bowl with it. The same thing could probably be said for ODF in a 2" bowl.A more shallow bowl with a wider inside circumference is good (as mentioned by an earlier post) for more complex blends, and with flake or plug, it needn't be a particularly short smoke, since a lot of flake or plug burns longer than loose tobacco.
I cube cut ODF and load it gravity fill in a Wade. Get about a 2 1/2 hour burn. I don't care for relights on ODF either, so my leisurely "me" time is reserved for that pipe/tobacco combo, or an Oliva Maduro and a glass of Glenfidditch.I would say my BW Freehands are close to a 2" depth, maybe 1.75 - 1.8125", I really don't know. I know you said you go back to a bowl & relight it throughout the day. I personally don't like to do that. I enjoy my ODF in a group 1 - group 2 size pipe with about a flake, flake & a half & start with a fresh bowl each time. Same thing with coins; I fold about 3 coins at a time in the same group 1 -group 2 pipes. They will still give me about a 50 min smoke or so.