I'll stick to Mike Hearn's opinion in his response to Greg :

Gregory, you are getting really crazy now. Stop it. The trend towards mining centralisation is not the fault of Gavin or myself, or anyone else. And SPV is exactly what was always intended to be used. It's not something I "fixated" on, it's right there in the white paper. Satoshi even encouraged me to keep working on bitcoinj before he left!


Look, it's clear you have decided that the way Bitcoin was meant to evolve isn't to your personal liking. That's fine. Go make an alt coin where your founding documents state that it's intended to always run on a 2015
Raspberry Pi, or whatever it is you mean by "small device". Remove SPV capability from the protocol so everyone has to fully validate. Make sure that's the understanding that everyone has from day one about what your alt coin is for. Then when someone says, gee, it'd be nice if we had some more capacity, you or someone else can go point at the announcement emails and say "no, GregCoin is meant to always be verifiable on small devices, that's our social contract and it's written into the consensus rules for that reason".

But your attempt to convert Bitcoin into that altcoin by exploiting a temporary hack is desperate, and deeply upsetting to many people. Not many quit their jobs and created companies to build products only for today's tiny user base."

https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-July/009726.html

So , good luck defending Greg's coin . Goodbye and have a nice day .