Well. in response to the title - I am likely considered too liberal considering I am DSA, but that is not the point I want to address.
RAZD, I have been somewhat following this thread and feel I understand how your strategy may be successful under some circumstances. However, I believe those circumstances are not presently as universal as you may believe.
You are In Rhode Island, not West Texas, so I would like to point out some other factors that diminish the strategy you propose in my situation.
These are the questions I would have to answer Yes to to have a snowball's chance in hell of even being a viable candidate for school board in this county:
1) Were you born in Howard County?
2) Have you lived in Howard County your entire life?
3) Are you a Southern Baptist or Church of Christ member in good standing who attends church regularly?
4) Do you like country music?
5) Are you a registered Republican and have been so your entire life?
6) Are you connected to the petroleum industry or cotton farming?
7) Do you have any vices? Do you smoke, drink, or do illegal drugs?
Here are my answers:
1) No, I was born in Fresno County, California in 1957.
2} No, not even the majority. My formative years were spent in San Luis Obispo County, California in the 70s. The minute I retire, the skidmarks I leave in getting the hell out of Texas will be noticeably visible until the road is repaved.
3) While a Methodist, Lutheran. or Presbyterian, may have an outside chance, they will be starting with one strike against in some voter's minds. Mandatory church attendance is non-negotiable around here. The best I could do is Unitarian Universalism, a deal breaker.
4) No, not in general. Shit, I am a deadhead (among other things), an immediate disqualifier.
5) No, not ever.
6) I am a librarian, worse I am a male librarian, which makes my masculinity and sexual orientation questionable around here.
7)

, critically read the above.
As you can see, any following of your strategy on my part would be impossible under the circumstances and it would be quite difficult even to find a proxy
My current purpose is to shift the Democratic Party to the left, at least for now, given the circumstances.
However there is a possibility for me to invoke your strategy in a statewide election. Dan Patrick is running for the Democratic nomination for the Governor's race in Texas, an automatic vote in the general. Should he be a shoe-in, there is one of those rare but purportedly reasonable Republicans running in their primary namely Scott Milder (oh, the irony), that due to considerable favorable remarks on the liberal side, might have my vote if Patrick is well ahead in the polls. Since this is an open primary state, in this one instance your strategy might be workable for my support.
Read not to contradict and confute, not to believe and take for granted, not to find talk and discourse, but to weigh and consider. - Francis Bacon